I have had my electric guitar for several years and I noticed that there is some "sweat dirt" on the fretboard of the guitar, so the inlay is less shiny.
I'd like to clean that without taking the risk of damaging the neck's wood or the fretboard's inlay.
As I know it's not a good idea to remove all the strings, I don't know if I should do that when cleaning. (Update: it appears that this is not true, see Bill Cheatham comment below.)
Moreover, I don't trust cleaning "packages" that guitar shops have the habit to sell as they are probably more expensive than regular products I could find in a supermarket.
So I'd like to know what kind of product I should use to clean the neck, what tools etc., and I'd like to know what should be the steps for cleaning the fretboard: removing all strings, remove some strings and cleaning half of the neck, removing the four middle strings, keeping only higher and lower strings....