Using a USB household hair clipper is a simple process, and typically involves the following steps:

1. Charge the clipper: Most USB hair clippers come with a USB cable that can be used to charge the device. Connect the USB cable to the clipper and plug it into a USB power source, such as a computer or a wall adapter. Allow the clipper to charge fully before use.

2. Choose the right attachment: Many hair clippers come with different attachments that can be used to cut hair to different lengths. Choose the attachment that corresponds to the desired length of hair to be cut.

3. Prepare the hair: Before using the clipper, ensure that the hair is clean and dry. Comb through the hair to remove tangles and knots.

4. Turn on the clipper: Turn on the clipper by pressing the power button or sliding the power switch to the "on" position. The clipper may have different speed settings, so choose the appropriate speed for the hair being cut.

5. Begin cutting: Start cutting at the back of the head, moving the clipper against the direction of hair growth. Use a steady hand and move the clipper slowly to ensure an even cut. If using an attachment, make sure to keep it level and flush against the head.

6. Clean the clipper: After use, detach the attachments and clean them thoroughly with warm water and soap. Wipe down the clipper with a clean cloth and store it in a dry place.

Always refer to the manufacturer's instructions for specific guidelines on how to use your particular USB hair clipper.