Foil highlights are perhaps the most versatile and creative form of highlights. The use of foils allows the stylist to place as many or as few highlights in whichever area of the head they choose. Cap highlights, on the other hand, limit the stylist in terms of placement, since the stylist is confined to pulling the hair through pre-determined holes in the cap. Another benefit of foils is that it allows a stylist to place multiple shades of colors in the hair at one time; something that is very difficult with a highlighting cap.
Is it possible to highlight your own hair using foil? It certainly is, but be warned: it is also very difficult to do on yourself. The keys to successful foiling are foil placement, color application, and processing time. Making a mistake with any of these variables will result in awful-looking highlights. Managing all three variables on your own will be very difficult.
Foil placement is the first thing to consider. Placing foils in different directions will result in different effects. Generally, you want the highlights around the front hairline and bang area to be the most noticeable, and the highlights in the back of the head to be more subtle. There are three distinct ways to section the hair which will go inside the foil. The first technique is weaving, which results in a more natural look. The second technique is slicing, in which a thin slice of hair is put into the foil. The third technique is chunking, which results is a large chunk of hair being put into the foil.
Once you have a section of hair to foil, you will want to use a brush to paint the color or bleach onto the hair. The moisture of your dye or bleach will make the hair stick to the foil, so there is no need to worry about clipping the hair in place onto each individual foil. If you are highlighting with a dye, you can apply the color pretty close to the scalp. If you are highlighting with bleach, however, you will want to stay about 1/8 of an inch away from the scalp. This is because bleach “swells” as it processes. Once your color has been painted onto the foil, carefully fold the foil in half, careful not to squeeze the color or bleach out of the foil.
Processing time is the final consideration. A permanent dye may need 30 to 35 minutes to process, while bleach may need only 10 to 15 minutes. It is important to unfold the foil every couple of minutes during processing to make sure that the hair is processing correctly. Hair that is fine will process quicker than hair that is coarse and thick.
Once the hair inside the foil is the right shade, carefully remove the foils and shampoo the hair, making sure to apply conditioner afterward.
This is, in a nutshell, how to foil hair like a professional stylist. Since professionals have to go to school for several months in order to learn this technique, don’t expect perfect results your first time. If you have doubts, it may be best to leave foiling in the hands of a professional.