Trust each other.
Be faithful.
Be honest.
Enjoy the time "together" (phone, Skype) talking about things that won't start
"a fight" or a big trouble.
Be honest to yourself: are the long distance relationship and the feeling you feel for being away from your love too heavy? It's supposed to be a bless, not a burden.
But you have to be sure that it's love. And that is not easy at all. =)