Hi Eve,
Look at some of the construction journals and members pics for ideas.
As for plants, small bromeliads, snake plants, and pothos are great for a Dumpy. Rinse them off well to remove fertilizers and any chance of some bug eggs that may hatch later on.
You will want plenty of branches or thick vines for climbing and places he/she can feel hidden.
Don't use any substrate that has something the frog can swallow. I use Zilla Jungle Mix and also Plantation Soil which are available at good pet stores and online.
Dumpys are usually very aggressive eaters and have been known to swallow sphagnum moss, stones, and anything else that happens into their mouth as they dive at a cricket.
If you go with plantation soil or eco earth, use a generous layer of leaf liter over it to reduce how dirty the frog gets.