Frozen
Good obviously you going to the swimming pool is an exception from you not being allowed a shower if you are still doing that task. However you may only rinse the shower and not wash.
1) Go into the changing room and take off your shoes first, then your shirt, then your pants and finally your boxers. Then without trying to cover up just casually reach for your swim shorts and pull them up.
2) When you've enjoyed your swim, leave the pool you will dry your chest and legs. You will then drop your swim shorts, then put your T-Shirt on again making no effort to cover your boy part. You may then slip your boxers on and then your pants. Do you rush and get it over and done with but perhaps draw attention to yourself or go more slowly, endure the task for longer and hope nobody looks.
3) Remember the order because if you do it differently you will fail the task.