After I get my GT Score up, I plan on dropping a Warrant Officer packet. What are the things I need to know to better help me?

Take time to prepare for the SIFT, pass a flight physical, take time to make good connections and get quality LORs, pay attention to the details of your packet, refer to the sample packet thats provided on the Warrant Officer Recruiting website, have it reviewed multiple times to ensure its error free. The list goes on.. more info here
https://recruiting.army.mil/ISO/AWOR/

It is my understanding at least from within my branches (MI and QM) that warrant packets include at least two NCOERs. Strong PT scores, strong NCOER's and probably a degree are your way to get selected. In your letters of recommendation (LOR) it will also require a CW3 (from what I've seen). Then the commander's letter of recommendation is usually thrown in there, so at best there is only one wild card LOR, which means probably just getting the highest rank you can find to give you an LOR (ideally someone higher than your company commander, or a CW4 or CW5 are probably even better than COL's).

Your path to success will be getting to E5+, and finding a WO to mentor you.

GT scores will improve each time you take the tests. Mine did as a result of a little study and help from extension courses.