Here is for everyone to learn little tips and contribute by posting their own tips. I have two tips I found out. Sorry if the tips I have are old.

*If you hear a Bullet Bill coming, move off to the side of the track. The Bullets Bills tend to stay in the middle of the track.
*When you go on those blue boost strip things on top of the walls, you can try tapping R repeatedly as you go and it seems to keep you on the blue strip extreamly well. One time I held R down and my character stayed perfectly on the blue strip, getting off multiple jumps without any effort.

Cool.

*You can move the bullet bill slowly to the left and right if you steer that way.

What do you mean the blue boosts on the wall? What track is that on?

The blue arrows on walls. They point up.

but what course is that on?

Good examples of this is Dk Summit and Waluigi's stadium.

When you get a lightning cloud, stop where you are and wait until someone passes by. Then chase that person and give him/her the lightning cloud.
Of course, if your close to the finish line on the final lap, try to reach it with the lightning cloud so you'd be able to finish before anyone else.

OH the half pipe stuff. You should have said that.

*If ur in first place and u get a triple banana item, keep all of them. u wont noe how many red shells will come after u.

*You can trick off the big green warp pipe on N64 Mario Raceway.