I feel the most important thing I can tell you about love and relationships is that words are empty if they are not backed up with actions. You can tell a person that you love them all day long but it means nothing if you ignore that person or don't SHOW them you love them.
Do not yell at your partner. If you feel that you need to yell at your partner then YOU have made a mistake and need to go back, slow down and calmly figure out how to fix it. If you are yelling, your partner is no longer listening and anything you are yelling about is just causing anger and damaging your relationship. Many people feel that they must address a situation at that moment. It's usually much better to wait until the next day when you are both calm. Take 24 hours and think about how you can get your point across without upsetting your partner.
Just as not yelling is important, you certainly must never swear or hit your partner!
Remember to thank your partner DAILY for the little things they do for you. I now try to make sure to tell my wife how much I enjoyed dinner. I acknowledge the time and effort that went into cooking the meal and tell her how much I appreciate it.
Don't lose who you are in a relationship and feel you must merge into one. You are both individuals with different viewpoints, like and dislikes. Just think about how boring it would be if you had the same thoughts.