Jon Kabat-Zinn's terrific "Mindfulness Meditation Workshop" offers instruction in a number of kinds of meditation, including sitting and walking meditation, and answers questions typical to both beginning meditators and experienced practitioners alike. The following excerpt is an example of how Kabat-Zinn makes meditation practice accessible to all of us.
If you are coming to this for the very first time or whether you have been cultivating mindfulness in this way for some time, letting go of the past and letting go of what is yet to come and not only acknowledging, but also directly encountering the fact that here you are right in this moment. So inviting yourself, as long as you are here, to be here 100%. Since the future and the past are not things that we let go of once and for all, and that is all there is to it. It is a continual retuning to the present moment.
For those of you who are totally new to it, one of the most friendly and convenient ways to embrace the actuality of being present is to tune into some aspect of your body and sensations that arise in the body. The breath is a very wonderful one. To just ride the waves of your own breathing in consciousness.