1. Create a new PPT document and click Open to enter the editing area, as shown in the figure below;

2. Place the mouse in the editable area of the document and click the Insert option on the menu bar, as shown in the figure below;

3. Select the desired pattern in the Insert menu, as shown in the figure below;

4. If you select a triangle and drag the mouse in the editing area, you can get the graphics you want.