The following is intended to be a set of clear and concise instructions that will help you begin meditating as quickly and easily as possible. Expect them to be characterized by a certain looseness, both to make it easier for you to adapt them to your situation and because in meditation over-instruction is worse than under-instruction.
Remember that you should never do anything with your mind the object of which you do not completely understand. If you have any questions or lingering doubts, make sure to re-read this article or seek additional guidance until you feel confident you know what you're doing and why.
It should first be clarified that in speaking of this as the "core technique" I don't mean that there is anything else we will be adding to it at any point. I mean that you don't need anything else to meditate other than these instructions, yourself, and a willingness to learn from your own experiences.
You're going to be sitting still for longer periods of time, so you're going to have to hold your body in such a way that it doesn't start to hurt. Find something that works. That is the entire rationale of posture.
For example, one thing that works for me is to sit on the floor, press the sole of my right foot against the inside of my left thigh (leg biceps), and touch the heel of my left foot to the shin of my right leg. If this is uncomfortable, sit any way that isn't. If possible, sit on a thick cushion because sitting up high tends to free up the abdomen, making it easier to breathe. You can also sit right on the floor or in a chair.
I rest the palms of my hands on my thighs with my fingertips touching the tops of my knees. If you don't like this position, put your hands anywhere that is convenient and where they'll support you and will help keep your upper body stable. Make sure not to put any weight on them that would put pressure on your wrists, because if you do, your wrists will hurt. Make sure that your shoulders are relaxed and your elbows are dangling freely. If they aren't, your shoulders will hurt.
Books often tell you to sit up straight, but if you sit up ramrod-straight, as I have a tendency to do, your back will hurt a lot. Some mild back pain is normal as you get used to sitting and will go away as your muscles adapt, but any really painful back symptoms are probably due to arching your back while you sit. Don't sit up at attention; you should actually feel a bit like you're slumping. To get it right, lean forward, arch your back, and then settle back into an upright position, relaxing your back as you do. Gently rock front to back and stop at the point where your trunk is balanced and tends to tip neither forwards nor backwards. Then rock side to side and do the same.
If your trunk is correctly balanced, you will have to expend minimal muscular effort to stay in that position. Regardless of how it may look in a mirror, your back should feel neither concave nor convex. When you're doing it right, you will feel as if your spine, flagpole-like, is straight and firmly planted upon the ground, requiring only occasional tiny adjustments to keep it that way. Check your posture frequently while you sit to ensure that you haven't inadvertently tensed up and that nothing hurts. When nothing hurts, you've got it right.
When you start, you'll still be getting to know yourself and your body. Mild discomfort is normal. You're not welded to the ground; the fundamental rule is: if something really hurts, move, find the problem, and fix it.
Look at a point on the floor about 12" (30 cm) in front of you. This is to get you tilting your head forward slightly. Don't fix that point with an unmoving gaze; just point your eyes in that general direction. The distance is only an approximation; what distance you in fact end up using depends on both the posture you select and your height.
You can keep your eyes open or shut; it's entirely up to you, but once you've made up your mind, don't go back and forth. The only difference in my experience is that shutting your eyes makes it easier to relax but harder to stay alert if you're tired; keeping them open makes it easier to stay alert, but you may have trouble relaxing. Over time these limitations can be overcome, so choose what works best for you in the beginning.
When you sit, the only rule is that there are no rules. Your practice has to be formless; following rules would spoil it. Nothing you can do is necessarily right or wrong. Every session will be different and require a different response. Only you can figure out what that needs to be. View trial and error as close friends.
That said, there are guidelines. What works for me is to start by focussing my awareness on the movement of my diaphragm as I breathe and to do this until I'm settled in. After a while I'll start to get interested in something else, and that's perfectly fine. Don't hold on to your thoughts and physical sensations; don't push them away. Be like someone watching leaves drift by on the waters of a stream. Be equally ready to move your awareness towards your mind and towards your body. Check your posture now and then to make sure you haven't moved, slumped over, or tensed up. Check your mind now and then to see what you're thinking. If you get lost and end up daydreaming instead of meditating, gently bring your attention back to your diaphragm for a bit until you're settled and you naturally start to get interested in something else. Try now and then to get a glimpse of the clear water, of the space between your experiences of your thoughts and your physical sensations.
Calming the mind is a waiting game, like waiting for sand to settle out of cloudy water: anything you could do to try to make it settle would just make it cloudier.
Don't try to stop thinking, and keep in mind that you sometimes need to think while you meditate. For example, it's common to reflect on your own practice while you sit; if you cut this off, you won't be able to use it to improve.
If I feel disturbed by thoughts rather than finding myself following them naturally, my rule of thumb is to return to the diaphragm no more than twice, and if I then find myself thinking the same thought, I go ahead and think it.
Also keep in mind that the diaphragm is like home base: it's not somewhere you're supposed to stay, but rather is somewhere you leave and come back to.
The ideal is to sit until it's time to get up, but this won't be possible for busy people. In that case I recommend setting a timer with a gentle bell. You can get one of the many meditation apps or just use the timer on your phone or watch as long as you can find a chime and a volume level that won't startle you. Twenty minutes four times a week will get you far and you'll know yourself when and if you need to do more. I'd say that an hour a day is really the absolute upper limit; 30–45 minutes daily is ideal for me. Some people prefer to have two twenty minute sessions per day, one in the morning and one in the evening. Personally I prefer to do one longer session sometime before my evening meal if at all possible, largely because I tend to be too tired to practise productively in the mornings and evenings.
I recommend sitting for at least twenty minutes each time. If you start with less than that and try to build up to longer sessions it probably won't work because there's a certain "knack" to silencing the mental metronome that keeps track of elapsed time, and you won't figure it out unless you have to.
Some people prefer to have fixed times of day when they meditate, while others prefer to meditate whenever it happens to be convenient on a given day. My preference is the latter.
Finally, the ideal is to meditate for just a little less time than you would like to. You should always be looking forward to and eager for the next session. You should never feel as if you've done too much. The very instant meditation starts to feel like an obligation instead of a pleasure, take a break. Try not to let it get anywhere near that point. Taking days off as you need them is perfectly fine.
Practise when it's time and keep boundaries between practice time and other time clear and distinct. Like the effects of exercise, any benefit you derive from meditation should express itself automatically and without conscious effort in daily life.
Basically, after almost every meditation session you should feel better than you did when you started. Each session should be easy, pleasant, and rewarding. Occasionally this might not be the case, e.g. if you're distracted, tired, or very upset, but if you're none of these and you feel discouraged or unhappy with your performance, stop right there and think about what you're doing wrong.
Usually what's happened is that you've mistakenly identified meditation practice with a very different kind of practice, the type that you do when you want to acquire proficiency in a new skill. Meditation, as I've been emphasizing, is different. It's true that there is some technique to learn, but you'll get as much as you ever need in a couple of weeks. There is no essential difference between someone who has been meditating for ten days and someone who has been meditating for ten years. Progress is not straightforwardly a function of time.
As you start to get into meditation, you might have all sorts of new sensations. I have experienced a vivid sense that I was sinking into the floor, felt a presence as if there were someone standing behind me, felt my eyes watering and saw the floor shimmering before my eyes, and so on. I've already told you how I sometimes see patterns in the carpet weave when I sit, much like seeing faces in a cloud, or dancing shapes in a flame. If you have experiences of this type, you should feel encouraged because it's a sign that you're making progress. Keep in mind that it will all go away, or else will stop being a distraction, once you get used to the new mental states you're producing in meditation.
Above all you must not try to buy your way into heaven. If you start to feel that you must practise every single day and you just can't afford to miss one session, then you should make a point of missing a session just to prove to yourself that missing a session doesn't make a difference. If it does, you've been doing something wrong.
Similarly, if you start to get the idea that meditation is bliss and would be even better if you gave up sex, alcohol, eating meat, or whatever, then you should probably make a point of having sex, drinking alcohol, or eating some meat. Don't misunderstand this: if you genuinely want to make lifestyle changes, that's a different story; but what you need to avoid is the idea that you can make your practice better by trading something for that improvement.
Your practice needs to be as free as possible of the notion of buying and selling, free of the idea of one meditator being better than another, and free of the intention to reach any ultimate end state. As I've been telling you, these and similar notions are based on misconceptions of the nature of meditation, and if you entertain them they will hold you back.
As with physical exercise, don't expect immediate results. Give yourself six to eight weeks at least and then assess your progress.
Finally, always remember that it is absolutely impossible to have a bad meditation session. If you couldn't concentrate, or whatever, it's probably because being distracted, or whatever, was better for you at that time.