How to select the correct snowboard based on rider size and abilities.

The two biggest factors in snowboard sizing are your weight and boot size. Height plays a very minimal role and only factors in when a board cannot support your stance. The general rule of thumb is to size yourself according to the manufacturer's provided weight range for each size (if available). You can size down if you are looking for more control, but the trade-off will be some stability. Size up if you want more float and stability, but the trade-off will be some control. For boot sizes 12US and up, look for a wide board with at least a 26cm waist.
Size Charts for Snowboards