So to skip the theory and get right to the practice, I figured I would use a Watercolor stain to form the base for the bookmarks, then go over the letters in acrylic, and seal it all in with some Super Sheen. I don't use the watercolor stain terribly often because it's A) expensive and B) stupendously messy. I have strategies and cleaners that work for every other stain in my arsenal, but leave any watercolor on any surface (even my silicon gluing mat) for more than half a minute and it'll never come out. On the upside, it's great at giving an even, smooth base coat that other elements can build on and it's infinitely mixable. Like most stains it's applied with a sponge and it's always a good idea to have ample water on hand. I usually use a silicone mat to keep my workbench as unstained as possible, but I've learned that watercolors will stain even that so I use sheets of parchment paper instead. It's important to work the stain into the leather with a little elbow grease so it can take awhile to go through 51 bookmarks.
Once the watercolor has cured overnight the painting can begin. Acrylic's a pretty straightforward medium and the trickiest part is mixing it to get the right balance between smoothness and opacity. Too thin and it goes on very smooth but just tints the leather. Too thick and it cures opaque but tends to clump. It generally takes 2-3 coats to get a good application and between my wife and I it took the whole weekend to get through the whole lot. Somehow I didn't get any pictures of us hunching with brushes in hand but the result came out pretty well.
The last step is certainly aptly named: finishing. Even after it's been tooled and stained, leather remains pretty susceptible to water, sweat, etc. So to keep it from degrading over time a finish is generally applied to seal the pores and fibers. Different finishes have different properties but in this case I'm using one called Super Sheen. As the name implies when it dries it leaves the leather a bit shiny. There's a few different ways it can be applied but I used a sponge to have more control and wound up giving the front 2 coats and the back 1 coat. It takes a few hours to fully cure between coats but the result is pretty nice.
As of this writing I'm still working on the second half of this order, 50 key fobs you may have noticed in the transferring post, but these bookmarks are on their way to their destination. Starting in November they can be purchased through the Talk Nerdy store. The key fobs are soon to follow as soon as they're complete. Thanks for talking the time to read through these posts and even if you don't have much need for a bookmark or key fob you should give Talk Nerdy a listen sometime.