The worst places to be in are when you've basically got no walls to help, either when you're on a thin bridge, or you're just balancing on two twigs. Of course these are still balanced so you can cross them easily enough, but if you're not careful you could fly off. Generally, being aware of the stage helps, and you'll notice parts of stages start repeating themselves eventually. Use your memory to remember each piece of the stage, and you'll clear them more quickly in the future.