My recommendation is always coloring hair the natural way with henna, indigo, etc to preserve your curls but if you still want to go the way of chemical colouring, these recommended oils will help protect your hair between applications and also make the colour last longer.

Life-Flo Pure Organic Safflower Oil

life flo safflower oil

Life-Flo Pure Hazelnut Oil

life flo hazelnut oil

Spectrum Naturals Safflower Oil

specturm naturals safflower oil

Eden Organic Safflower Oil

eden organic safflower oil

La Tourangelle Roasted Hazelnut Oil

la tourangelle roasted hazelnut