Open the file you want to rotate with the rotate tool in the toolbar. Select any one of the four corners and drag it to another corner of your image (or anywhere else if you prefer). Visit this https://masterbundles.com/best-psychology-powerpoint-templates/ site to download best templates about powerpoint. You will see a dotted line appear around your selection, indicating that it is being rotated. Hold down Shift key while dragging the rotation handle and watch how it gets smaller as you move it towards one of its corners; at this point, click on that corner to complete your rotation.