I'm a GM and half the time I hang on for dear life and follow the crowd. Any good Trial leader will explain what you have to do as things happen. Lambda took me ages to work out, and some of the others I just wander about hitting things. Great fun though. My favourite is Dilemma Diabolique, which is pretty easy to get all the badges and Master Of on. As long as you follow the instructions to the letter.
TF's tend to be a bit more "Blast through as fast as you can and try to keep up". Speed runs annoy me though as a lot of the time I literally have no idea what I'm doing. Zip, kill this person. Zip click this thing. Zip oh fight this AV. Done.
Edited to add, any good league leader is really helpful. DM them saying this is your first time and you don't know what to do and they'll make sure the instructions are clear.