Your guitar, mando, bass, banjo, violin, bagpipe, sitar, bajo sexto
looking a little dull?

I don't mean "dull" like that kid that was always in the chess club
that grew up to manage the local Radio Shack.
I mean "dull" like it's covered with fingerprints, sweat spots (yuk!),
dull spots where your big haired groupie got too close with her hair spray,
you know the routine. Typical guitar player stuff.

Polish that instrument!
Don't use Pledge or car wax or something with silicone. If you do
the silicone will make it VERY difficult for glue or lacquer to stick
to the instrument should it ever need repair or refinishing in the future.
Use something DESIGNED for MUSICAL INSTRUMENTS.

Whatever you use, don't use a lot. Use a tiny bit every now and then
not a lot all at once. Unless you routinely pour tequila all over your guitar
or do the Jimi Hendrix at Monterey imitation, you shouldn't have to polish it
more than maybe once a month.

Use the right combination of polish, wax, finish shine.
If your instrument is satin or matte finished (like many of mine are)
skip the finish shine but don't leave out the polish and wax steps.

There are a lot of blends, formulas, and styles on the market.
Chances are they are all pretty close in composition. As long as they
DON'T contain SILICONE, they should all be safe for your instrument.
Where I find a difference is in the ease of application and how long the
protection seems to last. A really hard, cake carnuba wax, for example,
is REALLY tough to apply. But it lasts for a really long time. But it's so darn
hard to apply and buff off that you end up not doing it for all the work it
costs. And if you don't get it buffed off well, it leaves the finish gummy
which attracts dirt and airborne goopyness. And everyone knows how
disgusting airborne goopyness can be!

Here's one of the products that I like.

Restore
From D'Addario/Planet Waves