1) to remind sb about sth = to help him/her remember it, as in:
For the math exam tomorrow, I'll have to bring my calculator with me. Please remember me about it.
2) to remind sb of sb/sth else = to make him/her remember or think about another thing, place, or person, because they are similar in some way, as in:
You remind me of a friend I met a few years ago in Paris.