Abigail is my dawg who dislikes the bath the most. Oh she doesn't mind the drying or even swimming but stand her in the sink and she just stands there stiff as a board. Is she afraid - well that's a good signal that she is but no - she doesn't shake - she just says - get that soap out of me.
She used to shake - arch her back and hide on me but she's over that stage now. They do get better and not all of them act like that. She's one of two that has - the rest doesn't seem to mind.
The point is - just do it as a matter of fact - give them kisses - keep your voice upbeat and cutsie pieish and give them a treat when they act like you want them to.
When I have a guest that is frightened, I give them treats and cuddles and play with them as I am washing and drying and it actually gets them enjoying.
The point is, help them find the fun. By helping them - you find your own fun.