I had hoped a couple of days to just find some map tiles to print and cut so we could play with them the same way we play with Carcassonne tiles, which is using them to make ad hoc town structures, mostly roads and sandboxes, and having the meeples invite each other over to play. Unfortunately, I couldn't find anything out there that was usable.
We did Plan B, which was to draw our own tiles on foam-backed poster board. My son is four, so I did most of the drawing, but coloring in green backgrounds was satisfying for him, as well as drawing the river bones and putting leaves and apples on trees.
We used tempera markers, which are ostensibly paint markers. They feel very waxy; in effect, it feels like drawing with lipstick. They are forgiving, though, in that you can paint layers to a degree. I had to do this a lot because we didn't have a brown marker, and brown is needed a lot in town landscapes.
Cutting seemed a lot harder than anticipated. I started with a box cutter, which seemed to mostly rip the paper, then tried a kitchen knife, then scissors. I then thought to open the box cutters with a screwdriver and flip the blade around to the still-sharp side, and cutting became smooth and easy.
It'll be interesting to see which tiles are popular. I made some rail intersections, which I thought would be used every so often, but the guy put them all together to make some weird mega rail grid.
If nothing, he's very happy that we have 150 tiles, good or bad!