Water

Every effort gets better, it just takes practice 

Finally had some time to test out a few techniques - many thanks for the responses below that guided my efforts!  I went with latex paint on a picture frame glass for the base.  Stippled in some ripples while it was damp.  The waves were dome with liquitex acrylic gel.  I did a base coat of tamiya sea blue and a top coat of tamiya clear blue.  The wave caps were drybrushed on in an acrylic white.  I think the wakes came out pretty good, the bow waves look a bit extreem.  Next time I will spend more effort researching true wave patterns, but this was fun and inexpensive.

I use a process similar to Monty's.  I start with a coat of Paynes Gray artists (tube) acrylic.  Good all around deep water color.   I will then mix some more Paynes Gray,  Pthalo Green,  or Ultra Blue acrylic tube paint into the Gel Medium to add some depth of color.   Color choice depend on where your setting is - Altantic/Pacific/Caribbean, etc.  Sculpt the basic water shapes & imbed the ship.    It may take a couple of days for a thick coat to dry - depending on temperature & humidity.   I may also go around and add some straight white for deeper wake froth (this gets toned down with the next step).   Apply some gloss medium tinted with just a bit of your water color and apply it over all.  This adds depth to the water and tones down the stark white.   Now go back and pick out white caps and tops of the bow wave & wake with some white.   Future floor polish is also a good wet looking finish.

The Gel Medium looks interesting.  Do you have an example of what the painted base looks like before you add the Gel Medium.  Also, how long does it take to cure before you can start adding surface details?  Do you need mix any color to the medium?  Finally, do you need to paint anything other than the white caps onto the dried medium?

Acrylic gel medium is what I've used in 1/700 scale; it comes in gloss and matt finishes. With care, it can be built up into reasonably high waves if that's what you want, and it gives a nice "depth" to the water when you put a base coat of greens and blues down, as with this Liberty ship:

Here is a diorama I did using clear acrylic gel on a blue painted surface.  I textured the surface to get the wake effects and the prop wash at the stern.

I had the best results for 1/700 to 1/350 using Liquitex clear acrylic gel. It is found at Hobby Lobby and Michaels.  I've applied it clear of a painted base and never had a problem.  I use oil paint to simulate white caps and wakes.

Depends on scale...1/700?  1/350? 

I have used epoxy and clear resin for large scale kits.  But I also used bathroom clear caulk for 1/700 and found it to work great.  For that I mixed in some cotton to form the waves on the bow and screw wake, then top coated with clear.

I guess you could use caulk for 1/350 not sure how much you would need for a BB or CV.

http://i649.photobucket.com/albums/uu218/sumterIII/ship4007.jpg

I've used vinyl spakling compound that is premixed. It can be smoothed on your base and sculpted to represent waves in a small scale. Once painted it looks great.

  And is very cheap.

Here are a few techniques I have tried.

- Rolled up aluminum foil, rolled pretty tight and then unrolled and glued to base.  The kinks due to rolling sort of look like waves.  The foil is then primed and painted.

- Acrylic gel medium.  Apparently there are several types- you want the stiff type.  This stuff can be applied very thick, and somewhat sculpted.  Perported to dry water-clear, mine was quite foggy- had to paint it sea color and then varnish the paint.  You get this medium at art or craft stores.

- Polyurethane varnish over sea colored paint.  You have to build up the waves with several coats to build them up very high.  Best for smaller scales, like 1:700 or smaller.

Here are some links a ship building buddy from my club recently sent to me.

http://www.shipmodels.info/mws_forum/viewtopic.php?f=4&t=38284

http://www.shipmodels.info/mws_forum/viewtopic.php?f=4&t=37641

http://steelnavy.com/WavePatterns.htm

http://steelnavy.com/Whitewater.htm