+1 It is usually best to leave it alone yet if you want to and are willing to take the time, this is the method I use and it works great.
This is an easy way to repair small dings if they are in the top or back, not so easy on a side of the bass. This is a Joe way, not a pro way, but if you take your time (about 30 minutes max) it will turn out very good.
Things you need:
1) Painters tape, the blue or green kind
2) 1ml Crafting Syringe
3) A small bottle of high quality ( opi or sparitual etc.) nail polish that matches the color of finish on your bass. That's easy because it's black but reds are more difficult because most people don't know if the red is more blue or more yellow as well as how light or dark it is compared to their finish until they see the contrast against the other paint.
4) Paper plates
5) Drop cloth
Put your bass on a flat solid surface with a drop cloth under it. Carefully tape off the ding, get the tape right at edge of the ding. You'll have to rip several tiny pieces. make sure you press each piece down with top of your finger nail around the edge so it's a good "seal". with more experience you can have the tape hang over the edges of the ding ever so slightly ( this is obviously size dependent) and it forms a lip on the ding and it makes it easier to get the edges of the nail polish to be level.
Shake the nail polish well and with two stacks of three or four paper plates ready, unscrew the cap and pull it out while wiping the brush that is inside and part of the cap (you'll see it when you pull off the cap) and set the cap on one set of plates and the bottle on another.
Fill the syringe with nail polish by drawing the plunger on the syringe up with the tip in the bottle, be careful not to knock the bottle over. Put the cap back on the bottle and set it aside.
Hold the tip of the syringe in the ding if it's bigger or over it if it's small and slowly push the nail polish out until the indent is filled. A deep gouge should be filled in stages to allow for better control over how much you put in. A good quality nail polish will self level, don't over fill it. After you fill it and it levels leave it alone, let it cure over night and then take off the tape.
It will dry with a gloss finish and if you fill it with the correct amount it's hard to detect without either inspecting the bass for flaws or knowing it's there.