Google "Dermablend"
Personally when mine was bad I moisturised well then used Bare Essentials Bare Mineral which covered my psoriasis well but left my face looking quite natural. You could build up the coverage as you needed it. There is a nack to using it but if you go somewhere like Debenhams they will show you how to "swirl, tap and buff" Its quite pricy but lasts ages and certainly made me more confident. Once you know what shade you need etc you can get good deals on it from QVC.