I love this hidden feature in Photoshop.
Next time you are retouching an image and want to rotate your canvas temporarily hit “R” on the keyboard.
To select tool hit “R” on the keyboard or select the rotate tool (it’s located under the hand tool).
Place tool cursor in the image window and click mouse.
Move the cursor clockwise (or anticlockwise) to rotate the canvas.
Hit ESC to revert back to the original view.