How to Make and Manipulate Triangles with GeoJr Press Small, Medium , or Large buttons to create a small, medium, or large triangle. Then press a color on the color bar to change it's color. Place 2 triangles next to each other and press the Magnetize button to attach the 2 triangles together. Use the Clone or Delete button to make another copy of a shape or delete it. Use the Rotate Left, Rotate Right, Flip Horizontal, and Flip Vertical buttons to rotate and flip shapes .