Most Helpful Guy
There's not really a way to practice kissing that isn't kissing.
Anyway, you'll be fine. Just relax and do what comes naturally. The only way to screw up kissing is to try too hard.
Most Helpful Girl
Practicing is really the best way to get better. Gauge how much tongue and force with it your boyfriend leaves, then kiss him back accordingly.
For example, if he's really active with it, you can let him 'lead' so to say. One person is usually the more passive, while the other takes over.