You have to be very "ngeh ngeh lai" and authoritative when
bathing difficult cats. Here's how:
1. Fill tub with warmer than warm water (it gets cool by the time
you get the cat to sit in the tub 
), and get ready the shampoo, a good absorbent towel,
etc.
2. Close all windows in the kitchen and the room where the cat will
end up after bathing (to avoid drafts, and make the experience more
pleasant for your cat).
3. Hold the cat firmly and take him to the bathroom.
4. Close and lock the bathroom door.
5. Grab the lower body of the cat (near the front paws) firmly, and
start pouring a small amount of water on him.
6. Talk and pacify the cat at the same time, all the way.
7. Bathe cat as per normal - shampoo and rinse - quickly!
8. With one hand still holding onto the cat, gently press/squeeze
out excess water from the cat, from front of body right down to the
tail.
9. With one hand still holding onto the cat, place towel in your
lap, place cat onto towel and wrap the cat up like a popiah.
10. Take cat to the room (with windows closed), close the door and
dry the cat.
11. Release cat and give him some cat treats.
Good luck!
ps: you may suffer a couple of scratches at the beginning, but
things will improve as you get better at it and the cat get used to
the bathing. 
