This is based on my past experiences, information from books, magazines and websites. Hope they are helpful to you.

1. Use a concealer a shade lighter than your skin tone or foundation when covering blemishes.

2. Always use a brush or cotton bud when applying concealer to spots to prevent infection.

3. Invest in a good blending brush. It's the best way to apply and blend concealer evenly.

4. Keep your brush unscrupulously clean by washing it regularly with warm water and facial wash.

5. For longer lasting coverage, pat on a little loose powder with a clean brush or powder puff.

6. Dab the concealer on spots and blend gently from the center.

7. To even out blemishes, apply concealer to spots or red areas and blend well into the skin. Finish off by dusting some loose powder over face.

8. Tilt chin downward when applying concealer to the under eye area. Apply concealer in dots along the dark circles and blend gently outwards using a brush.

9. Keep concealer light especially around the outer corner of the eye as wrinkles easily show up, even on young skin.

10. To prevent over-applying concealer, you can apply it on top of your foundation so that you can see which imperfections still need camouflaging.

I find mineral concealers much better and I guess it is better for your skin as well. Mineral foundations are also great - some of them melt right into your skin and it looks very natural. I would recommend it.