First rule of relationships: Always be honest

Always be honest
Telling each other the truth is key to surviving, Lies only breed trust issues in a relationship.

Dont forget to Communicate
Tell each other anything, no matter how uncomfortable. weather it be about money, Sex (especially sex), Needs, or even just communicating about everyday stuff when there's no "issues" to be discussed.

Be best friends
There is no relationship if you cant call each other friends. I find this rule to be the easiest one. If it's not there, if you cant have a good time hanging out and being friends, whats the point in pursuing a relationship?

Always show affection
Try to keep it fresh. there's no way you'll last if you lose affection for each other. Ladies, men like to cuddle, just not after sex. Set aside a different time for cuddling that isn't related to sex, and i guarantee that you'll get your cuddle fix, and he wont mind a bit.

Always accept them for who they are
If your with a man/woman your determined to fix, or change, or polish up a bit, your in the wrong relationship. I love my man, and that includes his nerdy electronic fixation, sometimes appalling manners, his inability to handle hard liquor without turning into a big baby, and his silly fear of clowns. There's no sense in wasting your time, Love all of them, or leave them. It'll be better for both of you in the long run.

Never let friends interfear in your relationship.
I've found that when most relationships are new, the friends of both parties feel left out, and sometimes even jealous. Never let this be a source of fighting between the two of you. it's not "bro's before hoe's", nor do "girlfriends last forever, and men come and go." we are a species designed to breed and have a family. This would never happen if we lived by these philosophies.

Never do anything you wouldnt want them doing.
I've made this mistake, and it doesn't feel very good when they come back at you with the comment like "how would you feel if i (fill in the blank).....?" Actually i went a little crazy inside when i imagined him staying out all night for "work" with a co-worker of the opposite sex. Needless to say, i haven't repeated this offense.