How to use this gel. The flaxseed gel works best when used on damp hair. So, after you have washed your hair, towel dry it and apply the gel. Make sure you apply it on your scalp, the shaft and ends of your hair.he flaxseed gel works best when used on damp hair. So, after you have washed your hair, towel dry it and apply the gel. Make sure you apply it on your scalp, the shaft and ends of your hair.