Some quick guitar questions

[PikeyPriest]

Firstly, does anyone have any adive for learning sweep picking? I`m trying to teach myself at the moment, but it seems hard to keep the left hand moving quickly enough to get the right sound. Are there any tips..etc to make it easier or is it purely a case of LOTS of practice?

Secondly, whats the best thing to clean the fretboard? I have noticed dirt building up and im not sure what is the best way to clean it without affecting/damaging it. Is just polish and a cloth okay?

thanks for any advice