By Laura Snyder

Back when you first started dating your girlfriend, you tried to impress the pants off her (literally!). But then things got comfortable, and you thought it was okay to take it easy on those thoughtful behaviors that made her swoon.

Not so. If you want to stay in her good graces - and in her bed - you'd better not slack off in these key areas. (The good news: You don't have to help her pick out the "perfect" pair of black heels among her closet full of seemingly identical black shoes.)

New Boyfriend Behavior #1: Interest and Attention

Once upon a time - think back - you used to actually pay attention to what your girlfriend was saying to you. But then you started tuning out...probably around the time you thought you had her all figured out. She still thinks communication is important, so you're going to have to at least act interested. Ask her about work, her friends, whatever she's into. You might not care much about the answers, but your attention will score points.

New Boyfriend Behavior #2: Hygiene

Back in the day, you'd never let her catch you with your gut hanging out in grungy boxers, eating day-old pizza out of the box in front of the tube. You were still hitting the gym, hitting the showers, and getting a regular shave and haircut. Where'd that guy go? She wants him back.

New Boyfriend Behavior #3: Out-Of-Bed Affection

You were all over her back when you were still trying to lure her into bed. But now that you've achieved that goal, you think it's okay to take the touchy-feely stuff down a notch. But she still wants - needs, even - the kissing and the hand-holding, even when it doesn't precede or follow sex.

New Boyfriend Behavior #4: Compromises

When you were still trying to impress her, you were a little more flexible about, say, what movies to rent or where to have dinner. But after settling into coupledom, you may have started to resent giving up your independence and are feeling a lot more reluctant to bend. Unfortunately, you're going to have to if you want this relationship to work. Both sides need to meet more than halfway on some of the issues, so suck it up.

New Boyfriend Behavior #5: Her Satisfaction

While it might be hard to maintain that clothes-ripping, bed-breaking enthusiasm you two shared when you first started hitting the sheets, it's important that you don't start slacking off when it comes to her sexual satisfaction. Translation: No skimping on foreplay and no falling asleep as soon as you've had your fun.