As said, a kick serve goes from 6 O'Clock to 12 O'Clock, while a slice serve usually goes from 7 O'Clock to 1 O'Clock or 8 O'Clock to 2 O'Clock.
7 -> 1, more power and less slice.
8 -> 2, more slice and less power.
The grip is the same, however for me the wrist release is different. It's hard...