Define a pattern and use it in a shape
Open up a picture that has the pattern, or texture, that you want to use. If you have a favorite type of paper, you can scan it in and work with it. For this example, I'm using my ancient, blue carpet.

Choose a selection tool from the tool menu. Since the patterns are all stored as rectangles, I recommend using the rectangle selection tool

Draw a square over the pattern you want to use.

Select Define Pattern from the Edit Menu.

Give the pattern a meaningful name and hit ok.
Create a new file.

Select a shape to draw. Use any shape you want. In this example, I used a flower-like shape.

After you draw the shape,go to the Layer menu and select Pattern from the Change Layout Content option. (Layer -> Change Layout Content -> Pattern)

If you just created your pattern, it should show up as the default and you can just hit ok. Otherwise, click on the pattern icon in the Pattern Fill dialog box, find your pattern, and select it.

