Ensure the trimmer has a fully charged or new battery. If necessary, attach the appropriate trimming head for the desired area (e.G. Nose, ear). Turn on the trimmer, possibly by sliding the power switch or pressing a button. Use the non-slip surface to hold the trimmer firmly and steadily. For nose hair, gently insert the trimmer into the nostril and trim the hairs using the LED light to see better. For ear hair, carefully trim the hairs around the ear using the non-slip surface for better control. After use, clean the trimmer head by rinsing it under water if it's waterproof. Dry the trimmer before storing it away.