When I started formal meditation practices (to see what was going on with various things I'd experienced over the years), I started with zen and zazen meditation. It was a good place to start because there are essentially no instructions other than "just sit". This prevents the mind from looking for things and focuses your attention on the present moment experience. So here's how to do it:
1. Take an upright sitting posture - assume the sitting position, relaxing but upright. This is very important as the body becomes the meditation practice.
2. Just sit. Pay attention to the rising and falling of the belly.
3. Keep sitting. The mind will wander off - bring it back to the rising and falling of the belly.
4. Allow the mind to calm itself through the body breathing.
5. Sit for as long as you can.
And that's it.