Here is a copy of what I posted about a month ago on the topic of cleeaning and waxing Brightsides paint.  As noted below, I think waxing varnish is equally beneficial, and highly recommend it.  It helps keep the topcoats of varnish from oxidyzing and becoming inelastic, which is the whole point to making the finish last longer.

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For cleaning, just about anything that isn't too agressive.  Dawn or Lemon Joy is always fine. (We always used these on long sailing trips as our "whole body" personal washes - they'll lather in salt water, and if you squeegee yourself with your hands and towell dry immediately after a rinsing swim you're actually quite clean and not too salty.  After a week or two your towell will smell like the bottom of the ocean - but there's no helping that other than a fresh water wash, and this is all a topic for another day.)  Back to the boat: Avoid aggressive detergents.  Warm water helps.  A big sponge and then lots of rinse water.  Of course, avoid anything abrassive.  Towell or chamois dry if avoiding spots - no different than washing a car, really, except nothing that equates to tar remover around the boat.

In my opinion wax is great for making and keeping painted (and varnished and gelcoat) boats looking good.  DO NOT use wax (or any finish) on any paint or varnish that isn't at least a month old.  I suggest avoiding the "modern" clear-coat types of teflon or "wet look" and other synthetic coating stuff - I think they "sink in" to the paint and mess with the ability to re-finish, and are generally very hard to buff out.  Also, I'd avoid any combo wax that says it includes "cleaner." In my opinion the more Carnuba the better. UV protection helps extend the life of the paint.  If you want to spend extra $$ you can look for wax for fabric covered airplanes.  Not sure it is really better, but it is good and you get some claimed UV guarantees with it.   If I took the liberty of recommending something, I'd go with Meguiar's Gold Class Carnuba Plus in the paste wax form. The Plus supposedly includes some synthetic polymers that add UV protection and extend time between waxing.

Stay out of the sun when waxing, mostly to avoid difficulty with the buffing! Buff just as soon as the wax is dry and has hazed over, even if this means you find some wax spots still a bit soft and streaky - if so, go over them a few minutes later, buffing more than once.  A very lightly damp rag can help on the first buffing if you're having trouble getting an area to buff out.  Using big terrycloth or micro-fiber towells and frequently finding fresh (without wax residue on the towell) areas is helpful.  Washing the towells afterwards makes them ready for next time.

Of course you'll have to ensure wax is removed before attempting any re-finishing, but by the time you sand and wipe with solvent prior to a first coat of epoxy or paint or whatever this shouldn't be a problem.

And finally, teach the youngsters about "elbow grease" - many hands make light work. That always helps, as well as repeating the good old mantra, "Wax on, wax off."

If you can't tell, yes, I've done this before.  Perhaps too many times...

If the boat lives outside it may not be a bad idea, but otherwise I wouldn't waste the effort.  If you do wax, don't apply anyplace that you will step because it will make it very slippery.  The former racing sailor in me will tell you to not wax below the waterline becuse it will make you a little slower.   

Huh?

I guess you could. But i'm not sure why. I varnish with a good marine varnish to provide UV protection. I use the boat. It travels in the sun on top of the truck for weeks that trun into months. It goes through lots of water, gets scratched and often re-varnished once or twice a year.

The wife uses her fiberglass/gel coated boat the same and waxes it. Scum often sticks to her boat. The same scum slides off my slick varnished water line but sticks to hers. I'll take varnished no wax.