When you have a deep pimple under the skin, it can be difficult to treat. The best thing to do is to start with a gentle cleanser that does not contain any harsh ingredients or fragrances. Next, apply a spot treatment specifically designed for treating acne that contains salicylic acid or benzoyl peroxide. Leave it on overnight and in the morning use warm water and your fingertips to gently massage the area around the pimple so that it can draw out some of the oil and debris from beneath the skin's surface. Finally, follow up with an over-the-counter hydrocortisone cream or aloe vera gel as these will help reduce inflammation and redness caused by acne lesions.