OK! Brushes and tools!
I used a random assortment of large, medium, and small, cheap artist paintbrushes here. Nothing special or fancy, just like the kind of assortment you can get in a plastic bag off the rack at Michael’s or equivalent craft supply store.
The paints were similarly a random mix of different brands of cheap acrylic craft paint. No sense using expensive miniature paints here. I used only six colors: White, black, brown, green, blue, and an orangey-yellow.
I got some apple juice bottles out of the recycle bin (my daughter drinks a ton of apple juice so we always have a lot of these) and used them as mixing pots. Tip: always mix up a big batch of each color in an airtight container, so you have plenty to paint multiple projects with, and you don’t have to try to recreate your color matches later.
My “Dry Sand” color started with the yellow-orange. I added brown to desaturate and white to lighten. I just mixed it by trial and error, adding more white if it was too dark, more brown if it was too saturated, until it looked like the photo.
“Wet Sand” is the same with less white and more brown.
“Light Seawater” is an equal mix of blue and green with a tiny dab of black. “Dark Seawater” is the same with a little bit more black.
Painting: my base surface is MDF (medium density fiberboard) from Home Depot. It has a rough side and a smooth side. I painted the smooth side. I didn’t sand it, prime it, or do anything special like that, I just started painting. I thinned the paints with water just enough for the brushes to stop leaving visible bristle lines in the brushstrokes, but no more than that.
I measured 10" up from one edge of the board (because 10" is how much water Dark Tide scenario #2 specifies) and marked both edges with pencil, then I drew a wiggly line between them. This way both boards, and any future boards, can match up when placed edge-to-edge. The shoreline can do any crazy wiggles in between as long as it starts and ends at the 10" mark.
On the inland side of that line, I painted about half the board with dry sand, then wet sand up to the wiggly line. I went for a fairly sharp dividing line rather than blending, because on a real beach the line between wet and dry sand is pretty noticeable.
On the ocean side, I painted about 1/3 of the way up with dark seawater, then the rest of the way with light seawater. Along the border I blended light and dark together into a gradient, by wetting another brush with water and smearing the two colors of wet paint into each other.
Finally, once all that is dry, I did the white seafoam. This is the part that really “sells” it as looking like realistic ocean, so this is the place to put in the effort. I took a smaller brush and watered down some white paint until the brushstrokes were pretty translucent. You want some of the underlying sand color to show through, because sea foam isn’t totally opaque. And you never want to paint a smooth line - it looks much too clean and artificial. Instead, stipple it - jab the brush randomly here and there along the line so that you get lots of random variation - more opaque in some spots, less in others.
If you look at the reference photo you can see there’s 2 waves. The earlier wave has already gone as far as it can up the beach, spent its energy, and is starting to recede, with foam and water trickling back down to the ocean. At the same time, a little further out to sea, a second wave is just cresting.
For the cresting wave, the shoreward side is pretty sharp, but the seaward side is more of a gradient. So while the light seawater color was still wet, I blended the white into it by dragging the white seaward with a wet brush and randomly stippling with water to do a purposefully messy wet blend.
For the receding wave, I stippled a front line a couple inches onto the “wet sand” color, then dragged paint backwards in random, wiggly rivulets towards the edge of the breaking wave. I made these rivulets randomly split and merge with each other.
And that’s pretty much all I’ve done so far. I also mixed some green and black and stippled a wiggly line up near the top of the beach to be the pile of dead, rotting seaweed that you always find at the high-tide line (that’s everybody’s favorite part of going to the beach, right?) but it’s optional.
