I'm struggling to get the brush settings right for this type of colouring and blending. Any tips?

Was just about to post a similar topic. Avast gets a false positive as well. The problem seems to be with ''ngsw-worker.js'' file but I don't know that stuff really:)

This worked for me. Try Menu > Settings > General > Exceptions Add 'www.proko.com' to the exceptions

A good start. It's also good that you've started using a skull reference. As someone who tried to learn drawing by starting out with the manga/anime style, I would actually recommend learning via the traditional style first. This is because anime style uses deformation of facial/body features; when in reality beginners need to learn the proper proportions, structure and anatomy first, or it would be difficult to see where the mistakes are as they are hidden in the stylistic deformations. As the saying goes, learn the rules first before bending the rules. Certain anime styles are also rather 2d and it would be difficult to learn from them as we need to understand the 3d forms. I'm not dissuading from learning anime style, but it would help perhaps to split the time set aside for drawing into 2 modes, one is a disciplined mode - learning anatomy via the traditional style, the other would be your leisure drawing - using the anime style or anything that strikes your fancy. For 3d reference, try using one that also has skin and muscle overlay that can be toggled on and off. There's a free website https://www.zygotebody.com where this can be done via the sliders. If you have instagram, I would recommend looking at taco1704 . He has anime/manga style tutorials and tips that more closely follow realistic proportions. It's in korean, but the images are so straightforward that it's easy to follow along regardless. He has also published a book that's on Amazon. If you get too bored or turned off with traditional style, this type of tutorials would be a good inbetween. Also, if you haven't drawn the skull yet, I encourage you to try doing so! As the skull is the hard bony structure that does not change regardless of expression, learning how the skull looks in different views will help toward a baseline for understanding the facial landmarks.