Use your time in STX lanes to learn and make mistakes. The results won't really "matter" back at your school, and in the scheme of things, not so much at Camp either, but you'll want to do well there. Make your mistakes in training, with other cadets, before it is with your unit and Soldiers.

I officially joined ROTC my Junior year after doing Basic Camp at Fort Knox. I then spent a semester in DC and had to cram all my MSIII tasks into one semester. Most of the ROTC instruction was classroom driven, but STX lanes actually get me out and moving. STX lanes don't have to be elaborate or even out in the woods. You can be creative and work out your SOPs and Tactics walking a dozen feet. Learn the basics there and get used to operating in a tactical manner.

You will be evaluated at Advance Camp, or whatever it is called now, before your senior year. You will take a squad of people you've known for 3 weeks and lead them through mock combat operations. You'll need to know land nav, tactics, movement, and how to work with a team. I was lucky and had a great squad. Everyone had a strength and helped out the current squad leader. Some squads didn't get along and were in competition. All you can do is learn as much as you can and give it your all regardless of who is in charge.

I commissioned and became a FA officer. I spent 5 months at OBC, learning how to do fire support and gunnery. We spent one day doing land nav and one day doing "dismounted and mounted" fire support. I showed up to my battery after airborne school and my second day we jumped into a night DZ mission and 3 day FTX. We focused on basic infantry squad tactics because we expected a non-standard mission to Iraq. I knew the baseline of FA, but I fell back on my ROTC and STX lanes experience and led our Soldiers through their lanes. They had no idea who I was, other than the new 2LT, but I seemed to know what I was talking about and from my MS4 year, I knew how to lead training.

I spent 3 months doing FA, then our battery received a convoy security mission and I became a gun truck platoon leader. We spent the next 6 months doing squad and platoon infantry ops and convoys. We deployed and did our mission for a year, and upon return, I moved to the HQ battery. I never saw a cannon again during my time in FA. Unless you go Infantry or Armor, you probably will get little actual "combat training" prior to arriving at your unit. I know TRADOC has implemented BOLC II, or is now incorporating back into OBC curriculum, but regardless, it is only a few weeks. Once at your unit, you won't have time to learn FM 7-8 and the related tasks. (But you can always refresh what you already know). Take advantage of the time now to learn OPORDS and TLPs. Learn tactics and techniques. You owe it to your future Soldiers.