I can second the use of one of these.
They can print in different type faces and print sizes. And you have a choice of coloured tape including clear.
Have also used mine to label the wiring. And other bits & bobs around the boat incl radio call sign etc.
Just beware when using them in places exposed to sunlight as the typeface disappears over time. However, used it down below and the radio callsign label (3 years old now) is as good as new.
yes, they are great but do not stad up well to light, rain, "the elements". However you can actually tape them over with some waterproof "duck tape" and get more life out of them like that
Hi Nickcred, for making up wire tags and general labelling I would recommend the system mentioned by Dave_White above. If you want to protect them against UV, i.e. externally, then do what we do at work and varnish over them with a UV filtered varnish. We actually use nail varnish from Boots but not sure about the UV protection (or the wifes reaction). The varnish also stops them peeling off.