hardy

I just fitted walnut in my bathroom looks great but still not happy with corners on window thought about mitre the corners but hard to do double mitre at top and bottom. Do you find the classic colours sand better than the darker colour or just use finer sand paper (wet and dry)? If I use a fine grit sandpaper the finish on the face of the tile not the same as factory honed and filled would I get this with wet and dry paper.

Cheers lads