I did it to my neck on my Fender Strat last year by first using a stripper like Nitro Mors (you should mask your rosewood fretboard with masking tape), leave it for a while then lightly take the finish off with a scr@per. I then used very light sand paper -1000 or 2000 grit- to give a smooth, bare finish. Then I sealed it with Tru-Oil about 5 or 6 times, leaving to dry well between each application. Then I finished it off by using wax.