The color result of any henna application will be highly distinctive due to differences in base hair color, thickness and texture. An important henna dyeing tip is to always select a shade lighter than the color you are hoping to achieve, especially if you’ve never done henna before. As an example, if you want dark brown hair, then the best to start with is medium brown henna. The reason for this is because you can always go darker with multiple applications; you can’t, however, go lighter.
Sometimes to achieve the right shade, or to get rid of henna’s inherent red tint, multiple applications are necessary. You can reapply henna as often as you like, giving at least 72 hours between each application. The 72 hour window is there so that the henna has enough time to oxidize in your hair. Henna rapidly oxidizes following the initiation application and will often deepen in color during this time window.