Good advice from Lowtimer and Kazbird, but they've forgotten the most important thing - Have Fun!
There'll be tough times - particularly when you come to try to land - but if you stick with it, you'll get to the good times, like your qualifying cross-country, the day you get your license, and the best of them all - first solo.
I'd imagine you'll have lots of questions as your training progresses. Everyone has different questions, so it's difficult to give general advice, except to never be afraid to ask.
Oh, and one other thing. You say you are going to start on Saturday, but you've already had a trial flight? Well, in that case, you've already started! The trial flight it a lesson in itself, you can log it, and you've probably learnt a load of stuff about attitude flying, how to fly straight and level, what each of the controls do, and so on. So already you're on your way to becoming a pilot!
FFF
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