1/3 Dettol
1/3 Metho
1/3 Baby Oil
and a few drops of *pure* Citronella Oil.
You don't have to be precise with the D/M/BO quantities, just use what you've got but stay as close as you can. The Metho helps repel, the Dettol helps repel and disinfect any bites, and the BO just helps the consistencyof the solution for application.
Mix up big quantities in put into spray bottles. I've got 2xlitre bottles for the camp, and various smaller ones for the car, boat and tackle box.
Cheap as chips and works a charm. I'd love to give this a go in the West Coast and Highlands of Scotland. Midgies are ferocious there, but at least there are no mozzies.
Good luck,
Mike