Here are some popular BMX tricks you can do.

Bar-turn
Turn your bars to the left or the right. Turning the bars to full 90 degrees gets you extra points.

Kick out
When back wheel leaves the jump, you can swing the rear to the right.
Gradually, sway the rear out farther each time you jump.

One-footer
Simply take your favorite foot off your pedal. Then, kick it to the side, and stick it back. Be sure to get it back in time. It requires a lot of practice.

One-hander
Pull up hard on your bars. Keep the bike in near-vertical position. Take hand off now. It is quite simple. Isn’t it?

Can-can
Perform much like one-footer trick. However, here, you should take your leg across the top tube of your bike.

Cross-up (X-up)
Do this trick only when you can spin your handlebars all the way around. Now, lean back and stretch legs apart.
Next, turn your bars a full 180 degrees, and "whip" them back in the reverse direction.

Tabletop
Push down to the right on your handlebars, and turn them down to the left simultaneously. It should be done when you push the rear of your bike up.

No-footer
Take your feet off just a few inches, and then pull them right back in before landing.

360
Start doing this on the ground.
At least, you must be able to do a 180. When you are about to bunny hop, initiate turning before your bike leaves the ground. Turn your head, and handlebars to either left or right. This trick is not easy, and requires a lot of practice.
More than reading these tricks, you should practice them.