The Citadel Colour Site is Fantastic
What a great resource the site has become. I spent some time over there exploring today with the latest email from Games Workshop and this site has really expanded outwards with tons of resource videos to really find more about the Techniques you want or need to use to your models painted.
Lots of techniques here whether you are preparing to do something new, doing research or just trying to brush up on your skills. I know I will be spending more time over there.
https://citadelcolour.com/