I am in week 1 of COT. I have some ideas you may want to jump on. Since they were major challenges this week.
Get your uniforms complete!! Get you name tapes and rank sewn on your ABU's at all costs. Do up the buttons and get strings off. Wear your boots!!! I wore mine hiking a couple times and still my feet are bruised.
Get yourself some kind of portable web link device. Mine is from sprint. It costs $60 a month. Money well spent. No one else can get online barely.
Bring a printer, extra ink, paper, scissors, tape, etc. Be prepared.
There have been some really amazing challenges already and there are more to come!!