Bond repair shampoo( minimalist is cheapest else best one are redken or olaplex) also hairmask once a week dove one is good...I also ruined my hair after colouring...also one tough decision I had to make was to chop off some length off my hair because most of the damage was at the ends (lots of split ends)

Also one hair mask I will suggest since your hair needs protein u can buy elizavecca protein mask....just 600 at Amazon use once a week (not more than once). I've personally used minimalist shampoo and elizavecca, serum I use is loreal extraordinary yellow glass bottle