First decide if you are going to go natural or a painted finish. Either way you are going to have to seal the grain with sanding sealer. After that lightly sand with 320 grit or if you want to go nuts wet sand with 400-500 grit. now if you are going to paint I would prime the neck out with two coats of primer, wet sand with 600-800 grit between coats, then start with your flat black finish coat. Make you coats light ! many light coats yield a much better finish than trying to cover in one coat, lightly sand between each coat. Then use a flat or satin clear coat over the finish, again lightly sanding between coats. If you go natural sanding sealer, then sand as above, then clear( gloss or satin) coat lightly wet sanding between coats. Or the real easy way is to sand the neck down to bare wood and us tungue oil on the neck. Just wipe on let dry, light sand, wipe on etc. thios will give the neck a nice natural feel. Hope this helps.