Here are some answers to a few questions I was asked:
1. When on dance floor, always mark the front wheel. This is because the back end of the dolly tends to shift around during movement and is rarely in the same place twice. I also generally mark the front wheel on track also just because it's easier to glance from the actors as they're moving, down to my marks. I do have a friend-a very good dolly grip-who marks his back tires. It works for him but he's been doing it for 20 years. I don't recommend it for anyone else.
2. Be prepared to abandon the marks. Actors will sometimes overstep, short, or completely disregard their marks. You have to adjust with them. Don't go through the move with your eyes glued to your marks. It ain't about getting from 1 to 2.
3. If you lay a track to the "lay of the land," in other words, not level from end to end but straightened by eye, don't get yourself in trouble by leaving too much slope. Bring the low end up enough that you don't have to strain every fiber of your being to push it. This is when they usually add a boom to the shot and you end up pushing uphill with one hand and booming with the other.
4. If the camera height they want in the blocking is at the bottom of the boom height, go ahead into low mode. They always want it lower. Trust me on this.
5. When possible, keep the operator over the dolly (chassis on the left).
6. Learn and remember the eyelines. If you don't know this rule., look it up. Knowing which side of camera an actor will be on will save you time in the setup and you won't look like a greenhorn asking where the dolly goes each time.
Hope this helps