You should not have WATER under the sink. If you are asking how to pretty it up? Contact paper, and keep it tidy. Any shelf paper, and change it out every few months. Plastic basket any supplies,

The door is closed..........we hope.........99% of the time.

In the meantime.....rid yourself of the "water" drip concern via a plumber.

Jan Moyer is correct . Talk to a plumber ..you can paint everything white ...and use contact paper ..as per her recommendation ...and make sure you close the door because this is not a pretty sight ...yet !

Why would you want to bring attention to what I would say is the worst cabinet in the kitchen

There is no water under the sink neither is there a "water drip". I'm looking to install an under the sink trash can and thought it would be nice to improve the ambiance of that gloomy place before it gets installed

I'd use contact paper that can be removed and changed out.