Hi Leoni.
Concealers should really only be used when, where and if necessary :-). Concealers come in different types and textures but I must say I favour a creamy concealer. The secret to a good concealer is that it should be easy to apply, blend smoothly and stay in place. Also remember when choosing a colour it should be 1 shade lighter than your skin tone and foundation. When applying, you could either use a concealer brush or gently pat it on with your ring finger. Be very gentle on the under eye area. Try to blend it so that it brightens and evens out your skin tone. Next step you should set with a light dusting of powder. Happy concealing.