Last evening I drew a couple friends celebrating in the swimming pool, and I am very happy with how it came out:

I also tried to capture this photo of Chris Hemworth surfing through a tubular wave, which didn't come out quite as well:

It seems like the more effort I put into making water look realisting, the more it looks like something I would have asked my mom to hang on the fridge in 4th grade. I know the answer is to keep practicing and keep looking at reference. Probably it would also be easier to achieve with paint than colored pencils. Still - why is it this hard?