Reese Witherspoon recently confessed on Ellen that she has a girl crush on Kate Middleton, saying, "I would like to hang out. I'm not sure she wants to hang out with me…. Call me. Call me anytime." We get where she's coming from—whether you've moved to a new town, your besties are popping out babies and moving to the 'burbs, or you just want to broaden your social circle, almost all of us go through a time when we’re on the prowl for buddies.

But how, exactly, do you ask out a girl? "Don't fall into the trap of thinking that everyone already has plenty of friends," says Irene S. Levine, PhD, professor of psychology at the NYU School of Medicine and author of Best Friends Forever: Surviving a Breakup With Your Best Friend, "Friendships come and go, and more of us than you can imagine are interested in getting to know new people." So we tapped the experts for tips that are guaranteed to turn you into a chick magnet.

The best way to meet people is through friends you already have. Put out an email to your girls asking if they know anyone in your area who they think you'd click with. "Research has shown that if two people have a friend in common, there's a greater probability that they'll hit it off as well," says Rachel Bertsche, author of MWF Seeking BFF: My Yearlong Search for a New Best Friend. Plus, the mutual friend gives you a shared ground and basis for conversation.

According to a psychological phenomenon called "the mere exposure effect" we're attracted to people who are familiar to us. So if you join a class or group that meets on a regular basis, not only will you encounter people with similar interests, but the fact that you're seeing each other often makes you likelier to become buddies. "And it gives you a natural reason to hang out," Levine adds. Asking someone from yoga if they want to go to a class with you, or grab a smoothie after savasana is more spontaneous and low-pressure than planning out a get-together in advance.

It's not just couples who are meeting on the internet—you can make friends there too, Levine says. Meetup.com, a network of local groups, makes it easy to find people you'll probably mesh with, from fellow vegetarians to snowboarders. You can search based on your interests or zip code. There are also options that work more like online dating sites, where you create a profile and can scour a database for interesting people (check out girlfriendcircles.com or socialjane.com).

Organizing a monthly get-together—like a book club, cocktail club (where you try a new bar each time), or rotating dinner party—is a low-key, flexible way to connect. Invite anyone cool who you meet to join in, and encourage them to invite their friends, too.

Women tend to apply the same theories they use in the dating scene when making new girlfriends, but doing so can put the brakes on a potential connection. "Eventually the friendship has to be reciprocal, but in the early stages you're still establishing a bond, and it helps to be proactive," Bertsche explains. So text the day after hanging out to say you had fun, and don't worry if you're the one to suggest plans a few times in a row.

When you do meet up with a new girl, that initial conversation can determine whether or not she becomes a BFF. "If you listen to two good friends talking, you'll notice that they exchange narratives back and forth," Bertsche points out. "New people are much more likely to ask each other a series of questions—where are you from, what do you do—which can make it feel more like an interview than hanging out with a friend." So instead of just telling her you're from Nashville, add in a funny story about growing up there. Your chat will flow more naturally, and as a result you'll feel closer.

After you've had a successful friend date, keep up the momentum by planning another get-together. "Use something you have in common as an excuse to hang out again. Like if you both wanted to see the hunger games, text her about going to the movies," Bertsche suggests. Even better: bring up an inside joke, which is one of the markers of friendship. "Say you talked about how you both think the romper trend is ridiculous—send her a funny picture of someone in a romper."