You can create a custom brush by selecting an area in a photo. The brush uses a grayscale version of that selection to apply the foreground color to your image. For example, you could select a leaf and then paint using a fall color. You can also draw a new brush shape using the Brush tool. You can create a custom brush shape either from an entire layer or from a selection. A custom brush shape can be up to 2500 pixels by 2500 pixels in size.
To use part of the image as a custom brush, select part of an image.
To use the entire layer as a custom brush, deselect everything.
Use the painting tools to draw the brush shape and select it. You can use hard-edged or soft-edged strokes, or vary the opacity of strokes to achieve soft-edge effects.