John Gottman and "The Magic Ratio" -- 5 to 1 meaning healthy relationships have 5 times more positive communication than negative. Make sure positive comments outnumber negative ones by a healthy ratio. Gottman's is an easy guideline to remember.
A premarital counseling session will make you understand your roles as a husband and wife and help you prepare for yourselves for the marriage. Here is a list of questions that you can expect at a counseling session.