There is a top-notch chap on Youtube called The Terrain Tutor (well, his name's Mel, but we risk being drawn into a Wellington/Wellesley distraction). He has a plethora of wonderful videos for the enthusiast, and I encourage you to check out his channel. He has a true passion for the hobby, which he communicates beautifully. One of his great tips was for creating a textured surface for a gaming board using filler. It's a bit too late for me to apply this idea to my own land boards, as they are already coated with sand. However, I have long fancied making a naval board, but was unable to get my head around how to do it. When I saw this I had a eureka moment. I shan't detail the way I made this, as he covers that perfectly in his video.
The colouring is also simplicity itself; I laid down some dark greens and blues, let them dry, then coated them with a single slightly lighter blue, and let that dry, and then applied a protective layer of undiluted PVA. After allowing that to dry, I dry-brushed white onto the board. You can make out the greens and blues in the photograph, but in the flesh the whole appears fairly uniform. I am very pleased with that, because it means that those colours have gone on just right. The PVA is essential both as a protective coat and to provide a sheen to the majority of the sea. I drybrushed the white on after it because I was mindful of advice in Richard Windrow's Osprey book on Terrain Modelling.
I made a handful of mistakes there, so I want to highlight them for you. Do not drybrush to the edge of the board or you'll end up with a white perimeter. Don't make your drybrushing strokes long lest you end up with obvious areas that are clearly brush-strokes. I know it's tempting when using a brush! Take a break instead.
Here are a few photos of the board (you can make out some of my naval reading in the background). A small Soviet/Russian force (1/3,000s, though I forget which manufacturer!) is making an appearance: a Typhoon-class submarine (I have two more), and then every other Russian ship I have: a couple of Kyndas, a Kuznetsov, two Sovremennyys and a pair of Kresta IIs. I picked up these guys and a handful of (mainly American) NATO ships some years ago, but never got round to doing anything with them. Truth be told, I prefer my dreadnoughts, but I sent them off to a friend some time ago! Anyway, the diabolical capitalists are in the process of being painted, so perhaps some day they'll kick consarned Russky ass. Balance in the UK means being rude to both sides. :D