Um, the screenshots there are plenty self explanitory I believe.
Nothing fancy, just make your background a medium neutral value. Then start drawing with a dark color or black even.
As to brushes?
I used to be into all kinds of textural brushes, and fancy brushes, but I've found I'm moving to more of a simple set up for my brushes as well.
A brush is just a tool. Build the brush that works for you.
I tend to only use a small handfull of brushes.
Some kind of square brush or pallet knife type brush,
A round brush that bleeds or mushes paint together,
And another round brush that holds a more sharper edge.
Then I have some effects type brushes that are really more just simple soft airbrushy brushes.
That's how I've evolved to working up to now, who knows what I'll be doing in a year. There are other effects I like to do to add texture to a piece, so I'll add a scribbly scratchy brush, or a spattering brush now and then. I'll use these both at the very beginning of a piece, and then again at the end.
How to make all these brushes? That would be a whole new, HUGE tutorial, one for Photoshop brushes and one for Painter brushes. Something I don't have time right now to do.
But again, you can find this info in your software manuals, it takes experimentation on your part to find what you like for you.
Ya have ta get in the program and mess with EVERYTHING. In doing that you'll find things you like, things you hate. You'll find what you need for you.
As an artist, you should be an observer first and foremost. When you see stuff ya like and are drawn to, think it through in your mind how you might achieve that, then DO IT. You won't be perfect at it when you try, that's not the point, but it will help you grow, and as you do it more and more, you'll get there.
I hope I get there someday.
Wow, ya pulled a Yoda-moment outa me, and it all started with brushes! Sheesh!