You just need to know one thing:
DON'T DO IT, Its a waste of time really.
If you don't want them to sleep on your couch, or your jacket, or the clothes you just have been ironing and folding there is just one solution, find something waaaaay better to sleep on.
1. An expensive new black wool coat (your cat need to be grey, white or orange, black cats dont like black clothes they don't see their own hair on it!).
2. A super smoot blaket your mum gave you for Christmas.
3. Your wonderful and beloved leather bag, the one you don't wear of its raining becasue you want it to last forever.
Aich.... you can't live with them, you can't live without them!