This painting is varnished. Varnishing helps protect the art work from dirt and UV rays. However, it's still best to hang the artwork out of direct sunlight for long lasting color preservation.
For light cleaning a clean dry paint brush will work to dust off the surface. The top layers of varnish may be removed by a professional restorer or the artist (me) for thorough cleaning.
The edges of watercolor paper are still vulnerable to damage. I recommend framing the piece in a floating frame (similar to a box) without glass which will protect the edges but still allow you to view the work without the glare or cost of glass.
If you want to be extra extra careful you can frame behind glass- museum quality glass is pricey but it offers the best protection against sunlight and allows you to fully see the artwork without glare.
