As you should know, carp eat anything. Your best bait is asking people at the venue you're going to fish what bait is 'hot', but on commercials, i always take a tin of sweetcorn, a tub of pellets, and i love fishinga big lump of paste, but be careful to use a heavy bodyied pole float when fishing with paste, as it has an annoying habit of sinking the float, but a neat trick is to fish a couple of inches over depth, puta big shot on the bottom,near the hook, and the paste will lie on the bottom and not sink the float. Catmeat is another good one, but possibly the hardest hookbait of all to hook.
The list goes on, maggot, meat, caster, worm, bread etc etc!!!
No no no, should never lay on with paste, a crafty carp will easily take the paste before you notice a take at all! Plumb up accuratly with the paste just touching bottom and really you dont need shot then! If plumbed accurately it wont sink the tiniest of pole floats. As for carp baits anything will do. Someone suggested tomato skin to me a while ago!!!