How Do I emble A tank that has an area with water, and an area with land (for a garter snake)?

Garter snakes don't need a large amount of water. A simple bowl will do nicely & the rest of your tank can be whatever substrate you choose ( shredded aspen, news paper etc.) a secure hidin or two, a heat source (incandescent bulb/ undertank heat pad) & a secure lid to keep your snake from taking too many side trips.