seeking cat claw care advice

My cat gets his claws caught on the carpet and couch quite often and
this causes him discomfort. I would like to trim his claws, but I don't
know how to safely do that. It seems it would be easier to get him a
scratching post, but I haven't found one that interests him. I would
appreciate any advice on either claw trimming or sure fire scratching
posts. He is about 10 years old and just a great creature. I'd do
anything to make him more comfortable. Thanks in advance.

Pam