I have created a handout for the class, with the intention that it be thorough enough to follow without needing me to be present. I hope that is so!
If you choose to varnish your egg(s), DON'T wear gloves. I know this sounds odd, but the process really works better without. Set up a place for varnished eggs to dry (skewers set in Styrofoam work quite nicely). Pour a small quantity of varnish into one hand, and then rub it over the eggshell. When you have covered the shell, slide it over a skewer to dry. Once you have varnished as many shells as you want to, pour some cooking oil on your hands and rub them together to release the varnish. You can then wash your hands normally. You can add more coats of varnish once the first dries, if you so desire.
