Some time ago, I heard of perfume for the hair. I did a lot of research trying to find a recipe for a perfume spray and I kept getting something about a perfume candle with hard to find ingredients. (Myrrh anyone?)
Finally, I just looked in the ingredients of different sprays sold online. Looks like the most common ingredients are:
Essential oils (fragrance)
It seems simple enough. For straightened hair, a light oil like grapeseed may need to be added in greater proportion to water to curb reversion. That's just a guess.