The advice that the majority of people give to a newly married couple has to with communication. Why is this? It is because communication is one of the important aspects of a good marriage. It is not the only thing though.
Have you ever wondered how much our words have to do with communication? Only 14% of our communication has to do with what we say. 35% is tone and 51% is Nonverbal, which is body language, eye contact, posture, etc. Those percentages are surprising. They were found by doing research.
In order to have excellent communication in your marriage you both need to be on the same page. There should be no assumptions. Say things out straight to each other, express love, and counsel together with each other. These are a few bits of advice.