I learned a little bit because I knew a deaf girl in high school. At first, I kept accidentally saying "fuck you" instead of "thank you" because apparently those two signs are very similar.
I also learned a few sentences such as "please give that to me" and "you are very funny."
I don't remember exactly. I think "thank you" is an outward hand motion from the mouth, but she said "fuck you" is an outward hand motion from the chest.
My friend is pretty good with sign language (even though she's not deaf, she's just interested in it) and I picked up a few things, such as the alphabet and how to talk about potatoes.
My mom was deaf in one ear and she ran a camp for the hearing impaired, so I was quite fluent when I was younger, but I haven't done any signing in at least five years now.