Mike from Knotflying is right. Here's what I previously posted as a solution to how to shower in the cockpit, or on the swim platform:
1. Remove round screen from port hole in bathroom. Set aside as spare for use when other screens rust out. Use sky light with screen installed to vent.
2. Replace shower head (looks like a telephone receiver)
with an On/Off switch model. These cost about $8-13 and are available in RV stores but not stores. They come in white, silver and biscuit colors. Buy a silver one.
http://www.rvplus.com/phoenix-products-hand-shower-head-classic-bisqu-9-342b.html
3. Buy a Thetford 36670 Spray Station holder for $6. It sticks by suction to the fiberglass wall under the porthole in the cockpit. They come in white and silver, buy a white one to match your fiberglass.
http://www.americanrvcompany.com/Thetfo ... 4445.html#
4. Enter head and set shower water temperature where you want it, then turn off water flow at the shower head.
5. Snake shower head out the porthole. Exit head, open big glass door, and sit in cockpit close to dangling shower head. Insert shower head in Thetford holder (which should have been previously affixed to the exterior wall under porthole; refer to instruction #3 above as needed). Turn on water. Shower. Rub vigorously! Turn off water while soaping to conserve.
6. Hose hair, follicles, skin fragments and other debris that falls off your aging body down the scuppers. (remember to clean scuppers once a year, or just before you sell the boat.) For very large fragments of mung, remember you have a powered raw water washdown nearby.
7. When done, reverse process and drop your new shower head into the existing holder inside the head, which, is still dry and hair free. Unsuction the remarkable Thetford folder and put in a safe place.
8. If you want to shower on the swim platform rather than in the cockpit, purchase a shower hose extension(s). They come in 6' long lengths so you may need two.
9. The above procedure, while complex, does lend itself to having a cold beer sitting nearby during showering to ease the process. Leave cap on bottle to prevent inadvertent beer dilution during showering. Feel free to print, laminate and affix this step-by-step guide in the cockpit to ensure steps are followed in proper sequence, if several beers are needed to complete process.
10. Remember my wife's rule: Shower every Saturday, whether you need it or not!!
Detailed instructions, like above, for use of a composting head will be offered later. WARNING: these will not be for the faint of heart! Photos may be included!
