I'm guessing you're not facing a real kicker but a soft moon ball. They can be difficult because they look so easy and goad you into overhitting.
1. Don't move slow because the ball is slow. In fact, double your foot speed to get into correct position as quickly as possible. Move fast!
2. Bring racket back high; shoulder/ear height and keep distance between your body and ball. More distance than you likely feel is right.
3. Hit ball when it is shoulder high. Crush it!
4. Follow thru with racket below other arm; almost waist level.
Don't underestimate difficulty. These returns are much harder than they appear but can be so much fun when you get confidence. Not only does it put the server on the defensive it can also play havoc with his first serve.