You need to put the dog up on a table. Don't try to groom on the floor or in your lap. If you don't have a grooming table, I recommend getting one of those non-stick mats you put under an area rug. Put this on a table or counter and it will give your dog a secure place to stand.
The slicker brush may be too prickly for this girl. Try using a pin brush. You want one without balls at the ends of the pins.
A Poodle needs to be taught to stand quietly while it is being brushed. You should also teach your dog to lie quietly on its side. This is both a safety and a grooming issue.
You can start out easy and table train by praising good behavior and scolding poor behavior. Reward with treats when the dog stands or lies quietly. Pretty soon, though, the dog should get with the program. If she doesn't, ask again and I'll tell you some tricks for getting a Poodle to behave on the table.