How do I oil my fretboard?

[Arthur Sweeney]

Hello, I just picked-up a used Washburn 12-string acoustic, model D10S12. It has a rosewood

fretboard that needs cleaning/oiling. I do not know what to use. I have read online to use the

following: furniture oil, mineral oil, almond oil, lemon oil. Which one should I use??

Also, someone once told me to never remove all the strings of the guitar at once.

Is this true? Thank you for your advice. Most appreciated.

 

[Alexander López]

I recently had to clean a seriously dirty, gummed-up fretboard. The gunk got inside the inlays and builded up like the Alps! Hope you can see it in the before / after pictures.

 

Since no cleaner could get rid of it, I used the Dremel with a Nylon blush to mechanically remove the gunk and to get below the frets. After that, I applied a soultion of lemon juice and olive oil (2:10 ratio) to clean the intrincate inlays, and later I did the usual white Scotch-Brite and steel wool treatment. What do you think?