Burocracy
Business is by far the hardest part of art for me, organizing, finding out where my money is coming from and the like. I tend to have a lot of ideas on how to move forward in this area and then fall short on my personal follow through, but it's necessary and I am getting better, so I take comfort in that.
I've also been venturing into foreign territory when it comes to my art recently. I'll be doing several larger works in mediums that are less familiar to me than my typical pencils, watercolors, and inks which is very exciting! As well as that I've been practicing my digital skills, and found the ability to quickly redraw/recolor things GREAT for working with pickier clients.