Okay, here is the situation:

1) You are in the middle of a lake or a harbor.
2) The water is cold and you are in chest waders. (It will be pretty easy if you are wearing shorts or swimming trunks. LOL)
3) The closest bathroom is at least 15min away IF you are not padding against currents.
4) Your bladder is about to explode.

I was tubing in the middle of a harbor today and I thought I will die from a ruptured bladder. Any solutions or suggestions are welcome.
Thanks for all the answers. I will stay away and tell everyone I know to stay away from used waders from now on. LOL

1) Casually look around for boat traffic and scan the shores. (Self explanatory)
2) Get off your shoulder straps.
3) Roll your wader down but not low enough for water to get in. Make sure you roll your wader inwards. (Will explain later)
4) Secure your rod so both of your arms will be free.
5) Push yourself up with your arms, slip off your wader just enough for you to unzip and sit higher on your tube. (YES! It could be done.)
6) Casually look around and scan the area again.
7) In a very casual manner, unzip and make a happy golden rainbow! Make sure you don't look down and put your hands in a normal position. This is very important because when any guy looks down and positions his hands down there, everyone in the area will know exactly what's going on.
8) While you are at it, casually scan the area. If there are possible viewers, kick gently and turn the float tube.
9) Your main problem is now solved. Now, roll your wader back up a little so any drops or spills won't have any chance touching your clothing. If you rolled the wader the wrong way earlier, those drops and spills will now be inside of your wader.
10) Gently lower yourself back into the wader and roll the wader all the way back up. Keep your movements slow and gentle because you don't want any water inside your wader.

VIOLA! No one will ever know what just happened.