Getting reference letter from professors whom I took their class-should I make any impression except my grade?
If you are still in contact with these professors, visit them now and let them know your plans and that you will ask them for letters in a year. This way they know what is happening and can also give you any advice they think relevant. A conversation would be best (not emails) as they get to ask you a few questions if necessary. So, the first option in your last paragraph is best, I think.
It is risky to rely on the memory of professors. We are a forgetful lot for many things.