In this tutorial I will be only going in to how I paint the clumpy kind, as my last painting required a lot of it.
First off I use a hair like brush which is modified to have some random strands. I'm not entirely sure how to save off just one brush on photoshop rather than a collection, when I figure that out I'll probably post up a link to download.
For painting the fur ball I simply ran with 5 shades of blue, you will probably end up using a lot more colours when painting fur yourself but, I figured I'd keep things simple.
Finally I use a larger brush again and set the opacity to 50 percent and paint over the area again on the fur where the light is hitting to make it pop back out and and look like thicker clumps.
I hope this tutorial some what helps if you are struggling on how to start off painting fur. It may not be the perfect way to paint fur but I've seen some really confusing tutorials and I figured it be worth doing one on how I tackled fur.