I found this poplar tray at a discount store. It was completely unfinished wood and came with 6 plastic pots and herb seeds. I wanted the set for the wooden tray, but planted the herbs anyway. The tray or box is roomy and lightweight and I thought I could do something to make it useful.
Then, I lined the inside with some blue patterned paper. I painted matte medium onto the inside of the tray, lightly dampened the paper and smoothed it out on the medium. When the layer dried, I brushed on an additional layer of matte medium to seal the paper.
Here is how the tray was intended to look with the pots, but I am going to use it inside on my desk.