Tools:
Smudge can sometimes be useful, but you don't need it.
Burn/Dodge never use these, never ever, ever
When people start with PS they use those <a href='http://tinyurl.com/y42zurt'>alot</a>, so did I.
But after a while you learn why its a mistake to rely on them all the time.
Layer opacity:
Making things darker:
So that shadow area I made by
- creating a new layer
- paint 100% opacity black, or maybe gray, with a bit of blue in it
- then on the layer, you can adjust the opacity with a slider, till it looks right
I also painted on it with a low opacity brush, its been over worked really
Making things lighter:
same thing but use a lighter color, adjust layer opacity.
Brush Opacity:
Just paint it with a brush, that has a low opacity setting on the brush,
Like 2% to 15%, then scrub over the area till it looks good.
Try using HSB color picker sliders.
Hue
Saturation, you rarely need full saturation
B (Black I guess) Value, other programs call this HSV, to adjust light and dark of the same color
Brush style:
Just use the simple round Paintbrush and Pencil brushes
- adjust the size as needed
- adjust the opacity
After you block out an area at 100%, you'll be at 2% to 60% most of the time.
You will need to adjust the brush size and opacity 200 times, there is no getting around this.
Draw some boxes
Profit !!!
Pro artists use a stylus on a screen and can use the pressure sensitivity to alter the brush size and opacity.
The tools above will allow you to work with a mouse.
Extra Credit
When making things lighter/darker, don't add low opacity pure white or black.
Use a light or dark color.