I tried this with yellow jackets this fall. They were coming to my feeders. Both bees and jackets are so blame fast that you can't keep your eye on them. A cool day may prove better. It must either be blue sky or big, fluffy, white clouds to back light the bee. Then you have the problem of trees!!!! It gets almost impossible. I traced some bees coming to a feeder, watched and walked for 3 hours. They would fly incredibly high to get over a row of trees so that was the end of that. The best source I read said to triangulate. You don't really follow, you take a pad and pen and release and triangulate the lines of flight. I try that this spring.