Free Brush Set
Overview
During one of those ordinary after work evenings, I was sketching some of the character thumbnails, just one after another.
I like to explore new shapes and forms, and to generate something I've never created before. Speaking in general, I manage to capture interesting ideas when I don't restrict myself to anything specific. So I have no idea what I am going to create at all.
Frankly speaking, the characters were the most difficult part for me to draw in the past.
I feel much more confident in drawing environments, but I knew that if I struggle on with the characters I would develop my concept art skills.
And I hardly ever give up))
Production
So usually, I quickly drop some silhouettes on a blank canvas. (Fig.01) I like to work with the silhouettes, because silhouettes allow me to concentrate more on the design, than on technical issues such as a shadows, highlights, color and etc.

Fig. 01
My main production tool is Photoshop, but I would advise Alchemy to those who are interested in concept-art. It is excellent software for producing interesting shapes that could be used in order to create characters, landscapes, vehicles or whatever one needs.
I have my own set of brushes for Photoshop, though I only use few of them during thumbnailing. You can download them by clicking the link towars the top of the page.
Actually there is no best brush for painting it is all up to the artist. In this painting I used only one brush. I would suggest using the brush that suits your style and your needs.
Some people create masterpieces with one pixel round brush, and some spend too much time searching for magical brushes in Photoshop. Don`t waste your time, just draw more and more.
Whilst working in Photoshop I find that the tool preset menu is more useful than the right-click brush menu. (Fig.02) Right-click menu only saves the brushes, but the tool preset menu allows me to save the presets of that specific tool, such as painting mode, opacity and flow. Also tool preset simply saves my time, instead of right-clicking and searching the brushes on the list, I simply select them from the tool preset menu that is constantly open on the right side of screen.

Fig. 02