At clubs... sometimes its just better to follow their rhythm, move your hips with theirs (DO NOT THRUST BACK AND FORTH LIKE YOU ARE HUMPING). Move your hips in a circular motion like your hula hooping. Sometimes if I am grinding from the back and I want them to face me I pull back so they no longer feel my crotch on their butt and I side step to their side and usually they get the hint and face me so I can get close and align my right leg in between hers so we can dip it low closer and grind from front. You should watch these videos for grinding:
Sean Paul - Gimme The Light
Sean Paul ft. Sasha - I'm Still In Love With You
Generally reggae/dancehall is made for freaking and dancing. It takes a lot of influences from Swing dancing so if you want to get crazy you should learn Swing dancing and you'll be set because thats one of the main roots of reggae/dancehall.
Just remember if she is letting you freak her, you shouldn't be afraid to hold her waist/hips. If she dips it low then dip it low with her or stand still and let her butt rub up you when she is backing it up. Sometimes a girl might put her hands on your thighs when you are behind, just place your hands on top of hers or you can do what I like to do and put my thumbs in her pockets while the rest of my hands is on her thigh (if you know what I mean). A lot of this is hard to explain in words, the best way to learn is to just goto the club and watch people and do it. Experience is the best teacher...
I don't use fancy techniques too much and spins because most of the time at clubs it's too packed to even do a spin and if you pull it off wrong you look like an azzhole or fruity. Trust me, you don't want to look like either. If you truly want to do something fancy... all I can say is you just have to learn steps and body rolls. If you want to do crazier stuff take salsa class or swing dance. Oh and another thing if you feel insecure about going up to girls at clubs... about 80% of the dudes at the clubs are wall flowers, so that eliminates a lot of competition... half the dudes on the floor dancing near girls are probably just friends and you'll be surprised how many of the guys on the floor don't know how to dance... That leaves a lot of room for you.
PS. In a group of girls dancing together, go for the fat one or nastier one for fun and watch the hotter ones show you whats good.
