Any Advice For Pre $5000 Hallo Freeroll?

Hi, I'm currently seeking my own decent bankroll and I have been gifted a free ticket for this huge freeroll but there is 8500 players so its not going to be a ''walk in the park'' I need a bit of strategy for the second half pre-bubble as I'm really good at keeping my cool most of he game until the big blind meets my small chipstack and I get forced all in with any ace and get called by a-k is there anyway that I can avoid leaving myself in this horrid position? any help would be greatly appreciated