Are we talking Photoshop settings here? I'm so bad at Photoshop brushes. Every single time I have to check Google to even remember how to create one.
Sorry, should've elaborated more on those in the first place! Here's a quick rundown on the most important Photoshop brush controls for this kind of task:
- Creating your brush - draw the shape or pattern you want to use in black on white (or transparent) background, then go to
Edit -> Define Brush Preset, give it a nice name ("Sampled Brush 6" in my case), and now you have your very own custom brush!
- Press F5 (or
Window -> Brush) to open the detailed Brush settings.

Here, in the
Brush Tip Shape tab find your new brush, select it, and set the appropriate
Spacing.
Spacing sets the distance between each brush tip placed, so setting it low means smooth, unbroken lines, while setting it high means you'd see each individual brush mark separately.
- Now, on to
Scattering!
Scatter basically moves your brush marks around randomly, the higher you set it - the further apart they'll jump. Ticking the 'Both Axes' box would mean that your marks would scatter in every direction, making the pattern more random, but harder to control.
Count refers to the amount of marks being spawned
Count Jitter adds randomized variation to the
Count parameter
- For more customization and randomization,
Shape Dynamics is a good next step.

I won't go into detail about what all of these do, since it's easier to just try them out and see, but the general idea is that 'Jitter' parameters add some variation to different aspects of your brush.
Using this with the 'Pencil' tool for cleaner pixel art can be pretty problematic, since it mangles small brushes quite badly, but can still be useful for creating complicated patterns and shape edges.
There are similar controls for the colors in
Color Dynamics and for opacity in
Transfer.
And here's what it looks like when you just draw a straight line with these different settings - a picture is worth a thousand words, after all.