There should be trust between both the partners and it should not waiver at any time. A marriage, either love or arrange, without trust would never be successful
Be it arranged marriage or love marriage both the partners need to manage their finances well. Both should know the income and savings of the other and should plan all the investments together.
Both partners should take care of household chores. Even after having house help there are a few things which are needed to be done by the residents of the house. All such things should be equally divided between both the partners.
The most important thing one needs to manage is time i.e. time one should give to each other. No matter how much the partners know each other they need to spend time with each other to make the marriage work.
One needs to manage the family, as well along with the relationship. The family includes in-laws and their responsibilities. Even if the in-laws are living separately they are to be taken care off.
Do not criticize your in-laws. Treat them equally as your parents, give them time and meet them regularly.
Do not bring up arguments which you both had in past. It could ruin the relationship.
Be it about your past relationship or anything which your partner must know off, hiding it could result in an argument and can even break the relationship. Hiding is equivalent to lying to your partner.
Partners should be open to talking or sharing information with each other being in complete control of their senses. They should not take the help of alcohol or drugs to be truthful with their partner.
In a marriage both the partners should forgive each other over small arguments. There is no point in dragging an argument to an extent which would break the relationship.