If you want to learn about transparent layering o glazes you may want to get Salvador Dali's 50 secrets to a magic construction. Reviewing it now, it seems to owe much of its appeal to Dali's pretentious prose and characteristic love of absurdity. But the book has too little practical advice on matters of technique, paints, etc. How to sleep without sleeping, the correct way to point your mustache, how often to have sex with your wife and when, and a little note here and there on which colors to use and how to draw. He idolized Valasquez and thought his fellow modern artists were hacks.
Realism is the goal.
Would also appreciate any personal experiences, particully troublesome are the skin tones in portraiture. An orange or red glaze looks hideous, and pink does not seem to work. Someone suggested a golden brown, but did not possess any recipe. Dioxizine purple, ventian red, and burnt umber are good for shadows. You may want to use alizarin crimson instead of transparent red.