Ages ago, I wrote a blog post about my favourite adult colouring books. Adult colouring has become such a massive trend in the past couple of years, with bookshops having entire sections dedicated to colouring books. I love a broad range of designs, from big and simple to tiny and delicate. In today’s post, Sandra from onecolouratatimeblog.com is here to tell you about a different form of adult colouring that I actually haven’t heard of before. Without further ado, I’ll pass you over to Sandra!