I think you can wear just about any color with it. A little structure on top might help since the skirt is flowy and casual. I like the wrap blouse D posted. A button down camp style shirt might be cute too.
Mu problem is the waistband. A top would have to be fitted and tucked in, or loose enough that it doesn't look lumpy. I know the rule is volume only on top OR bottom but the bow tie would be in the way.
So I'd go with a slim knit on top, tucked in, in red, yellow, kelly green or similar bright color with tan/nude flats or sandals. Or white/bright tank under a cute solid cardigan. If you need to dress it up you could do so with a white top and navy blazer.
Or a white peasant-y looser top, perhaps showing some cleavage so you still look like you have a body underneath, and tall wedges. Espadrilles are a good call.
I was thinking a bright top as well. I think Kelly green or fushia or yellow would just pop with it. It's a casual, kind of laid back skirt so i personally would try to keep the same laid back vibe with it. I think espadrilles or simple nude wedges would be a good call.
If you wanted to funk it up a but, what about a graphic tee on top?
With T-shirts tucked in, but not too tight. Also a tank. LLayered tank. Roomy T-shirt. ( also tucked in) . Preferably dark tops. With either flats or middle heel booties (black booties, peep toe & closed toe). Or flat booties. Cute skirt.
Leotards - they have been my new staple as I am petite and short waisted and have a BIG problem with waist bulk. The classsic cap sleeve can be had for 13.50 and there are lots of new styles since ballet class circa 984. Check out dance wearhouses on line!