Also take into account what kind of kit you have. If you have a pro kit with high-end brands and great brushes, be sure not to low-ball your price. It's a fine line, but since you already have a portfolio built you can consider yourself an artist and charge accordingly. Also take into account if you will be staying all day for touch-ups. If you use airbrush you can charge more (though I have never been a fan of airbrush for weddings.) Doing wedding makeup is difficult and tough on the body, not to mention having to deal with nervous brides. I would call around and get an idea what others are charging in your area. That's the easiest way to get a good figure. Good luck!