I find that my grey hair can get a bit dull over time and, in order to keep the white strands vibrant, I use L'Oreal Silver shampoo specifically for grey hair about once a week (or just when I notice that it needs done). Having experimented with grey hair products over the last few years, my all-time favourite products are from a Nottingham-based company called White Hot Hair https://www.whitehothair.co.uk/. White Hot Hair was founded in June 2013 and provides a full range of hair products specifically for grey hair. I regularly use the Shampoo and Conditioner – they are amazing and smell beautiful. I also find that the Lifeshine Oil, used sparingly, gives a beautiful shiny finish to my hair and makes it glisten.
I find that the texture of my hair is quite fragile so I minimise my use of electric straighteners - when I do use them it's on a mid-setting to avoid damage.