Sica, I have the same trouble with Sammy. She just won’t hold still, and I can’t even get her up on a table.

I have found that she objected to a firm comb, but the softer brush wasn’t as objectionable, and she likes to toss it too. I have tried this:
I sit next to her on the floor when she wants some head pets. I give her a nice long head rub, get her relaxed, then gently move my hands down along her body for a full body rub and bring my hand back quickly so she’s still getting head pets. When she arches her back a bit she is relaxed. If you’re right handed, continue to do this with your left. With the right, take the brush quietly and gently follow your rubbing body hand with it. Or, continue to give her head rubs only as you run the brush along her sides with your other hand. Make soothing noises, like “good bunny” so she closes her eyes a bit. Also, if you cup her head in your hand while giving head rubs, you kind of block her view and she won’t see the brush coming toward her which is either an object to be batted or an invitation to play. She’ll just feel it.

Now I need to start a new post asking for help to get her on a table! LOL

I hold them in the crook of my arm with their head pointing towards my elbow…they usually will bury their faces in the fold of my arm and relax while I brush away.

I usually sit on the floor indian style with Felony trapped in between my legs. This lets me hold his butt down and comb out his mane, then when I’m done with that I put his head under my leg at the knee. It keeps him calm so I can brush the booty

Put them somewhere where they are not used to being- like on a towel on top of your bathroom counter.  If they are not used to being there they might be unsure enough about where they are that they do not try to get away.

Cotton has super fine thick fur- and she is pretty good with being combed- but every once in a while I have to get her tummy and back end and back of legs- and it takes a minute or 2 of intense combing and then I let her go.