Money matters : Before getting married, you have to decide what is more important for you - money or your partner? Most of the marriages break apart because of money issues. If one partner is a spendthrift, the other is very stingy. It is quite fine to be either but when you have to live together and share the money you are earning, it is very important to compromise on some aspects and not treat the money as "my money" or "your money".
Arguments : Arguments are quite common in a marriage when two different individuals, with different temperaments and characters come together. The key is to not let that argument turn into a serious fight or issue, which can completely break your relation. Avoid using harsh words in an argument, which can hurt the sentiments of your partner and create a fissure between you that cannot be mended.
Forget About The Past : If your present is happy and there was something in your past that was too serious to be forgotten, avoid bringing it up. Do not dwell on the past mistakes of your partner. It is best to forgive and forget.
Personal Matters : Do not, ever, discuss your personal matters with your parents and other family members or friends and outsiders. It is best to keep your personal matters to yourself as an outsider can take advantage of that issue and create a problem further. Even if you have forgiven your partner or they have forgiven you, an outsider can make it an issue of problem in the future.
Respect Partner's Space : If your partner wants to go out on his or her own or wants to spend some time alone, let them. Spending time alone does not mean your partner does not love you. He or she perhaps needs time to think something on their own.
Do Not Insult : Do not insult your partner in front of others, whether they are your friends or family members or theirs. It is important to respect your partners in front of others so that your partner is never disrespected or considers you the cause of the insult. Respect your partner.
Avoid Ego : I am right and you are wrong. This is a short sentence that can break apart marriages in an instant. There is nothing like right or wrong. Different people have different perceptions about things and just because you believe it to be right or wrong does not mean that the other person would think the same. Discuss, do not impose and do admit your mistakes if you have committed them.
Following the above mentioned points can definitely help you maintain a happy and healthy relationship with your spouse. Small things and small gestures mean a lot and you do not have to be perfect for your marriage to be happy, you should just learn to do things perfectly.