1 hour glucose test tomorrow

With my first pregnancy I had GD and I believe I failed because the night before the 1 hour test I ate ice cream and failed but I also failed the 3 hr but I don’t remember what I ate then when I failed the second time but I didn’t understand what GD was the first time around they almost keep it a secret from you and don’t give you much info like what to eat and what not to eat so my question is the first time I did the 1 hour test I didn’t eat before the test and I’m wondering since I have a history of GD should I eat or not before the appt and what should I eat? (I heard not eating can affect the results but I don’t know what’s true or not google is telling me 50/50 some say to eat and some say NOT to eat) ugh stressed already I really don’t want GD again it’s really just a pain in the butt