Find the forward/reverse button, which is above and slightly back from the trigger, and put it in the reverse position.
Grip the black sleeve on the chuck with one hand while you pull the trigger with the other. This expands the chuck into the open position.
Change the directional button to the forward position.
Slide a drill bit or a screwdriver bit into the chuck until the end of the drill bit seats against the inside back wall of the chuck. If using a screwdriver bit, it may not seat at the back of the chuck. In this case, seat it far enough inside the chuck that the tip remains easily accessible.
Hold the drill bit and black sleeve in place with one hand and press the trigger with the other. This will close the chuck around the bit. Exercise caution, as the bit will spin when the chuck closes tight.
Rotate the numbered silver sleeve on the chuck until you reach the symbol that has several diagonal lines if you are using a drill bit. This is the strongest torque setting and prevents the bit from stopping as you drill. Select a number between 1 and 15 if you are using a screwdriver tip. As a note, the smaller the drill, the lower the torque setting. This will help prevent the screwdriver tip from stripping out the screw head.
Press the trigger to drill or screw into the work surface. If you need to remove a screw, place the directional button in reverse and unscrew the screw from the work surface.