1. Get comfy, but not horizontal
    Sit in any position that's comfortable for you. You don't have to sit cross legged to meditate. Just avoid lying down, as you're likely to fall asleep that way.
  2. Start small
    Sit for just a few minutes when you're starting out. Just five minutes a day, done consistently, is better than trying to do marathon sessions, getting frustrated, and giving up.
  3. Don't beat yourself up for having thoughts pop up
    You will have thoughts while you meditate. The point is not to have no thoughts, it's to train yourself back to focusing on your breath or mantra whenever your mind strays.
  4. Expect that sometimes meditating will suck
    Occasionally you'll have a session that's just awful. Painful memories might intrude into your mind, you might feel restless and not be able to sit still. This is totally normal.