Of all the relationship strategies to master out there, for some reason, friendship seems to be a tough one. Getting to be good friends with your girls was likely a long process, full of drama. But making lifelong, good friends doesn't have to be a trial by fire. Like you might do in a romantic relationship, there are a few ways to sustain and enrich your friendship from the get-go. First of all, check compatibility. You'll do this by comparing your interests, energy, passions and motivations. Obviously an introverted person who likes quiet activities and a social butterfly who likes to go out drinking and dancing aren't necessarily going to spend a lot of time together. That high-energy dancer and low-energy bookworm are not the best pair. Once you decide you can be buddies, it's not a bad idea to set some argument ground rules. Fighting fairly in a romantic relationship is important, and the same is true for friendship.

Discuss your "dealbreakers" – would it be dating the other friend's ex? When do each of you feel comfortable speaking up when differences arise? Immediately? Or do you tend to sit on your emotions? It's essential to any friendship not to be the friend who uses the other one emotionally. Friends are there to lean on, but when one gives support freely while the other habitually takes it without returning support, then conflict can arise. Venting is OK when both parties are OK with it, but your friend shouldn't become your personal emotional dumping ground.  Both of you have lives and face conflicts, but it's important to balance your relationship with lighthearted, fun stuff, too.