1 and 2 are right. After that, email your professors to set up meetings or go to their office hours. I didn't ask for letters via email, just to set up a meeting to "talk about medical school". They probably all guessed what I was getting at though. After they agree, give them a deadline and check to make sure they finish the letters. Write them a thank you note and keep them in the loop after that about your application process and where you end up getting in and deciding to attend.