The biggest mistake women make is choosing a foundation that’s too light. This gives an unnatural, ashen look. Here are a couple of tips to practice when buying foundation.

Test foundation on the inside of the forearm-skin tone is closest to neck colour there, because it's protected from UV damage. Makeup should blend with the skin colour of the neck, not the face. 

If any doubt then buy one shade lighter than your facial skin tone. 

Don't make up your mind instantly. It takes about a minute for colour to dry and interact with the chemicals in your skin. The red pigments develop first so it will appear the pinkest at the beginning. 

Then go to the nearest source of natural light. (Even the most flattering uplit cosmetics hall tends to have colour-distorting fluorescent lighting.) If you have chosen the right colour, it will disappear into the skin. 

How to Use Foundation

Keep your hair off your face by tying it back or using a hair band or scarf. Cleanse and moisturize your face and neck. Wait at least five minutes for the moisturizer to be thoroughly absorbed into the skin. Sweep the sponge smoothly across the foundation. If you are using a cake foundation that needs to be applied with water, dampen a cosmetic sponge and squeeze out the excessive water. The more water you leave in the sponge the lighter the effect of the foundation will be; the drier the sponge, the heavier the effect will be. Using gentle, even strokes, cover the larger areas of your face first (the cheeks, forehead and T-Zone) following their natural contours. 

Blend well under the jawline and down to the neck to create a natural effect and avoid a tide mark. Be careful not to apply too much around the hairline. 

 Finally, check to make sure the face is smoothly and evenly covered. Check for any tide marks and merge them well.
Use a concealor on any spots or blemishes. You'll see that your face glowing without a spot .