Permanent marker remover: 65p from chemist (nail varnish remover) and cloth is 1 piece of ex-running shorts.
Old non-permanent pen remove permanent pen
or as HWD said a nice pencil eraser and a bit of spit (nice).
I don't even own a watch.... i use the windy uppy one in the cockpit or if i can't remember i use the club phone and ring up tower
