To twist the cube:
1. Select the «Twist» tool.
2. Click at a sticker of the cube.
Use the Alt key to do a counter-clockwise twist.
Use the Shift key to do 180° twists.
Use the Command key to do a double layer twist (Mac only).
To remove stickers from the cube:
1. Select the «Stickers» tool.
2. Click at a sticker of the cube.
Use the Shift key to remove stickers of the same color.
Use the Alt key to remove stickers on the same part type.
Use Alt+Shift together to remove all stickers at once.