Where are you going to "summer camp" at?
Some words of advice:
1. GET IN SHAPE NOW. be able to do MINIMUM 50 GOOD pushups/situps in 2 minutes. Be able to run 2 miles in about 14 minutes. Will save you alot of heartache later. Most of these kids are 18 years old and you are 26 (yes Forest, there IS a difference).
2. If you smoke or use tobacco, STOP NOW (because it's going to be even harder when the Drill Sergeant is stressing you).
3. If you are overweight, get it off NOW (nothing like being called a fatboy in front of your 'peers').
4. Be ready for mind games. You are older and hopefully more mature than your 'peers'. Some of them are going to act like fools (which you want to stay away from). Remember, it's the DS job to stress you to see how you will react and then they can mold you. IF you are older and act more mature, they still may mess with you, but if you can handle it you will have more leadership opportunities.
5. In the end, do EXACTLY what the Drill Sergeant says, WHEN he says it. "Nametag Defilade".
6. Pay attention to DETAIL.
7. KEEP CONTROL OF YOUR EMOTIONS.
It's an experience you will remember the rest of your life. I alway loved watching Day 1 ("get off the truck and get into the front leaning rest position NOW!)