Good Dye Young Semi-Permanent Hair Colour This Good Dye Young Semi-Permanent Hair Colour ($18) is the one to pick if you want your new hue to last well past October 31. Each of the nine shades offer professional-grade pigments in a non-toxic, peroxide-free formula so you can mix up vibrant results that last up to six weeks right at home. Image Source: sephora.com Good Dye Young Semi-Permanent Hair Colour $18 from sephora.com Buy Now