The most simple meditation is the breathing meditation. These days, it is part of what many people refer to as Mindfulness.
This word, mindfulness, represents people re-badging meditation in order to remove it from its more esoteric, new age, hippy roots. It's a way to make mediation sound more scientific.
I have a very unscientific take on meditation; albeit, a very analytical one. What's the difference? Science requires verification. Science doesn't like anecdotal experience. But, as someone who has been exposed to meditation since he was three years old, I've learned that the anecdotal, personal experience of meditation is what makes it work for those who do it. It's personal, and deeply so. Scientific research is just a nice reminder that meditation works. What science doesn't do is tell us how to make it work for ourselves.
How do you make breathing meditation work for you?
Breathing mediation has only two steps:
Step 1: Breathe in and breathe out, steadily;
Step 2: Simply keep your attention on your breathing.
That's really it.
Having said that, people can, and do, overthink it. A lot of what I've seen regarding people explaining it, can also result in over-teaching it.
That leads me to pitfalls to avoid.
Avoiding breathing meditation pitfalls
Pitfall 1: You must breathe in a particular way
No, you don't need to breathe in any particular way except one: don't breathe in and out through your mouth. You can breathe out through your mouth, but don't breathe in through it. It is unhealthy to do so. But apart from this caution, you can either breathe in and out through your nose, or in through your nose and out through your mouth.
You also don't need to hold breaths for a particular period of time, and breathe for a certain number of seconds. Just breathe at whatever pace feels relaxing for you, and breathe steadily. Keep the cadence of your breath even and calm. This includes it not being really deep or too shallow. Just do normal, relaxing breaths. You'll know what this feels like when you do it. Don't worry about other people having a different cadence or style. Meditation is personal and different for everyone.
Pitfall 2: How long to meditate
The second thing that you need to be aware of is that there is no golden rule for how long you should meditate for. This is true for any kind of meditation. I was taught to believe that two hours a day is what one should strive for. For many years, that's what I did. But I found that, after a certain point, I just spent a lot of time just breathing or chanting.
What I eventually learned was that you'll feel how long you should meditate for. You'll feel your body relax into it, and at some point, you'll feel your consciousness come out of it. Some days you'll feel like doing it longer than others. This is fine. Meditation does take a degree of mental energy, the same way exercising takes physical energy. In my family, we used to refer to mediation as Spiritual Exercises, and I think that this is correct in the sense that meditation is exercise for your mind. This means that you need to pace yourself and take it easy. Mediation should not feel like a chore.
Pitfall 3: Focusing on your breath
Many people really try hard at meditation, which is the exact way not to get its benefits. They do this by obsessing over the instructions that they're given. The most common is the idea that they must focus on their breath and not lose this focus.
No, its actually good to lose focus. For me, it's when my mind clears things and I feel a lot better. But while I think that it's good to get lost in thought, when my consciousness returns and I'm aware that I'm not paying attention to my breathing anymore, I return my attention to it. What I shouldn't do, is to continue to consciously focus on the thoughts that I was just having. That's what takes you out of the meditation.
In other words, pay attention to your breath but don't obsess over it. Meditation is relaxing and letting go.
Pitfall 4: Meditating position
People often speak of sitting up when meditating. But I've often found that lying down works better for me. The point is, pick a position that is comfortable for you. Again, we're all different and your journey is your own.