Care for coloured hair newbie pls!!

[FusionChefGeoff]

Recently decided to overhaul my hair with some gradual highlights. Love the look but absolutely hate what it's done to the condition of my hair!! Hadn't had it coloured for years and rarely heat styled so it was in ace nick and would brush ourt easily with minimum care. I use a refillable Faith in Nature shampoo and conditioner.

Now it's a horrid tangly dry mess and I don't know what to invest my time and money in to try to repair it??

Pre wash treatment?
Hair mask / oil when wet / dry?
Leave in conditioner / treatment?

I'm also trying to maximise my wave into a curl so anything that might help that is a bonus.

Anything that is vaguely ethical in terms of packaging would be even better.

Garnier hair food.
I used my when I had highlights and one mask made a massive difference.

That's great thank you.

I found some Aussie Miracle leave in conditioner so have dumped a load of that on for now.

Olaplex 6 SERIOUSLY
Also Kerastase shampoo and conditioner. I've tried so much over the years and nothing but these have strengthened and untangled my post menopausal dry and tatty hair.

Kerastase Reflection shampoo, mask and their Elixir rose hair oil on damp hair.

I've heard mention of Olaplex on other threads and assumed it was a salon treatment can you do it at home?

I'd like to keep my refillable day to day shampoo and conditioner so will try the Kerastase hair oil.

Olaplex works wonders on my bleached frazzled hair