Annie Sloan Chalk paint advice please

[MissScatterbrain]

This paint really does go a long way - have only used less than a 1/4 tin of duck egg blue and although the piece looks great in the room its in, I don't want to use it again in other rooms. What I can mix it with to get new colours?

Also the piece I've just done has a unpainted top - its oak, has stained and scratches so if I sand it, how should I seal and protect it afterwards?

Finally I need a very small pot of dark wax and don't want to buy AS's wax as the pots are too big. Any suggestions please?