Default How to get 4G speed from Straight Talk AT&T micro sim for my HTC One (M7) Verizon?

It's at Edge speed right now and I can't bare the slow speed. I'm about to travel to L.A soon to see my fellow friends graduate and I need the data to bus everywhere by knowing the directions to take via Google Maps.

I already S-Off my phone, unlocked bootloader, rooted, etc...
Is there anything I could do to get a faster speed besides getting another phone? I'm taking off tomorrow so I desperately need everybody's help