You need to practise the below on a daily basis. As scientifically proven, benefits usually kicks in after a few days only (and it gets better the more you practise, but you don't need years to start seeing results :-) )
Get into a quiet environment (later this won't be needed anymore but it really helps when you're a beginner), ideally a separate room or the garden, a place where you won't be disturbed for the next 10 minutes.
Take a cushion with you, wear loose cloths, and take a timer (kitchen timer, any alarm clock or mobile phone).
Set the timer for 10 minutes. Stay still until the timer rings.
Sit on your cushion, cross legs (you don't need the lotus or half-lotus posture, just take any stable sitting position you can hold for 10 minutes), pay attention to sitting with a straight back. You may close your eyes or keep them half-open (avoid fully open, too much energy going in); if you keep your eyes half-open, you should not focus your gaze on any object in particular (and even less so if it is moving or changing colours... so, do not watch the timer). To avoid falling asleep (believe me!), you may press the tip of your tongue to the top of your mouth and keep eyes half-open. Try to relax the jaws, but keep the mouth closed.
From here, there are two main paths (concentration and mental-noting). Below are instruction in relation to the first one. A common point of the paths though is about being present, not lost in thoughts about the past or the future.
The first way to meditate is #concentration , i.e. focusing on one single idea. What is commonly advised is focusing on the breath (main reasons are: the breath relates to the present here and now, it is a focus on something 'moving' hence it's easier as an anchor for attention, and it also opens ways toward the second meditation path).
You need to stay focused on how it feels to exhale and inhale, without trying to control the breath (e.g. force it slow), just observing: you might notice e.g. how the air you inhale is colder than the air you exhale, or e.g. how your belly moves too as you breath in and out.
What you might notice from time to time is that your back is no longer straight, and this doesn't help breathing. Without changing your sitting position in a major way, just adjust to sit straight again and continue.
What you might notice is that, after a few breaths, your mind wanders off. Not only it wanders off, but it does so about the past or the future, rarely about the present. It is extremely hard at first to stay present, and that's exactly what you need to learn to meditate (which might also turn helpful at night when you struggle to find sleep). When the mind wanders off, well, simply refocus on your breathing when you become conscious that you lost track.
Pieces of advise:
- Do not "wait" for the timer to go off. That's projecting yourself in the future... Do not think about what you will do next, or about what other people are doing right now. Just focus on the breath;
- Do not beat yourself up for not staying focused. This is how the human brain commonly works, this is not your fault if it loses focus, so don't blame yourself, just keep practising. Practice and a bit of discipline are what make things possible (just like going to school and learning how to write...);
- Most important piece of advice: when you become conscious that you're thinking rather than observing your breath, you can imagine yourself "dropping" the idea that was just busying you. Like you'd drop a hot object you'd hold in your hand. Not taking the time to put it aside, or on a table, or in a drawer... Simply dropping the object of the floor, here and now, immediately. Just drop it. Let it go, without taking care of keeping it for later. And focus again on breathing. Initially you might need to do this every few seconds... After a few days, you should get a couple more seconds in between each occurrence. Just keep practising... The few more seconds of silence could already be just what your brain needs (in other contexts) to listen more to the world and gain access new insights;
- The same ideas might come to your mind again and again. There is no point getting upset about them, that's just your mind telling you what's "important" these days among your worries or desires. Funnily enough after a few days, you might experience repetition, but about other ideas, and realise that what seemed so important at the time wasn't that important given how easily it was replaced by something else (now itself deemed important, until something else...). Just let them go, drop them, refocus on the breathing;
- Initially, meditation might feel like the mind is busier, not calmer. This is because you're being present to your mind and are now listening to it. Basically you perceive more of what was there anyway. It will calm down after a while, don't worry about it;
- The practise of "dropping" bothering thoughts is what you're after here. So if you drop an idea, and it comes back immediately, don't get annoyed, just drop it again. And again, if necessary... Once you learn (by practice) how to do it, how it feels to do it, then you'll become more and more able to do it at night with bothering thoughts, but also when plugged in by what somebody can say in a meeting, etc... in any situation where thoughts take over, you'll become able to drop the thought if it is not a helpful thought. It is a very valuable skill to have, that's how to avoid being upset (without turning anger into bad emotions we lock inside ourselves, which is what most people do when they control their anger).
Once you will have defeated delusion (that "having" some thing, some principle, some rule, some relationship will end dissatisfaction) and can drop any thought, you're free.