I normally just moisturise then put some foundation on. But since i was introduced to Smashbox primer i have not looked back. It seriously allows your foundation to just glide on, it enables the foundation to stay on longer, and it (so it says) fills in any lines and wrinkles....ive been so impressed with this stuff. Its a bit expensive at $60 a bottle, but i only use it on spec occassions....
Ive just got my mum and 3 x sisters onto a primer too.....