Color dyes will not bleed onto lighter hair if you use conditioner. Coat lighter hair with conditioner throughout the colouring process to protect it. When you rinse the dye out, the conditioner will function as a barrier, reducing the colour's undesirable contact with your hair. If you don't want to use conditioner, try using a product such as DevaCurl's Protect & Perfect or Garnier Fructis Anti-Frizz Cream. These products contain ingredients that help block the absorption of color into your hair, reducing the chance of a mismatch. Hair dye contains alcohol which dries out your hair over time. If your hair starts feeling dry after coloring it, you need more moisture in your regimen. Use a mild shampoo and conditioner and follow with a heat protection spray to preserve the color of your hair.