Lay down a sheet of wax paper.
Place a container at the center. Use a container (soda can, mason jar, plastic bottle, etc.) to form the center of your volcano. This is where you will mix your lava!
Use clay to make the rest of the volcano. Mold the clay from the base to the top of the can. Try to make it look lumpy instead of smooth, since real volcanoes don’t look like perfect cones most of the time!
For more you can refer to this site.
http://www.wikihow.com/Make-a-Volcano