You can create a new layer by clicking on the Window Menu on the top horizontal toolbar, and then clicking the “New Layer” button at the bottom of the box.
You will see that some of your brush options choose the size of the brush that you can use for freehand drawing, while others are automatic brush strokes in a variety of styles. You can also download more of these pre-set brush strokes from Adobe’s website or independent graphic design sites.
You do not need to set a color in the solid color box. This is a “fill” color, which is used to fill objects. In the case of brush strokes, you are drawing a line and nothing needs to be filled in.
If you are working with geometrical objects, hold down the shift key as you use a brush stroke. This constrains your stroke to a 45, 90, 135 or 180 degree angle.
Once you choose the type of brush that you want to use from the pop out menu, a box will pop up that shows you all of the types of brushes in that category.
You can also change the size of the brush stroke and the opacity of the object, by using the toolbar. This toolbar sits directly below the Menu toolbar on the top. Experiment with changing the brush stroke size and opacity when your stroke is selected.
