Welcome to the forum tomchey. Your question is a little vague, so here is my thoughts for you: START with youtube and type "sculpting techniques" and wach the videos. Next, get some water-based clay, It's about $10-$20 for 50lbs. Make/buy some basic tools, kidney, rakes, loops, etc. dont know how to make clay modeling tools? Youtube has videos on that.
Come back and tell how it went, and be sure to post pictures.