My tip is that if you have skin problems- scars, birth marks etc Use Dermablend
I have it and am using it for my wedding to cover a keloid scar- it also covers tattoos when you dont want them to be seen.
I think the most improtant thing my make-up artist told me to do before she arrive ( to do my make-up for my wedding in May) is to cleanse and moisterise with good products 30 min before, it helps everything "stick" better.
For my eyes I have a great product by Clarins called eye flash. Its a mositeriser that I put on before the make up, it gets rid of puffyness and helps hid dark circles- yes it really works, I used it under my make-up on a day that I was very sick and had little sleep and was dehydrated (think, black puffy eyes) in my grad photos you can not tell at all that I was sick