Reduce swelling in order to level the skin surface
Rub the area around the pimple with an ice cube (wrapped in a soft cloth, direct contact can damage the epidermis) for 5 minutes or with a wad soaked with Visin eye drops (causing constriction of the blood vessels).
If you have more time, try with paste of powdered aspirin and some water. Apply it on the area and let it stay overnight. Aspirin contains salicylic acid, which has an anti-inflammatory effect. However, this method is not recommended for a sensitive skin.
If the pimple is leaking or festering, but not yet ready to pop, smear it with cream containing healing and soothing active ingredients (zinc oxide, vitamins A and E). After you squeeze the pimple (or it pops by itself), hydrate the skin around it with healing and moisturizing cream, to remove excessive dryness and flaking of the skin, caused by the previously used products. Suitable are formulas with aloe vera, calendula or lavender extacts.
Cover pimples and redness
Choose a concealer with dense texture and apply it on the pimple with gentle tapping movements (avoid spreading it on the surrounding skin). Keep in mind that lighter shades will make the pimple more visible. You can use a makeup applicator for more precision. Finally, fixate it using your index finger pad and smooth it with foundation.
To make sure that the pimple will remain hidden and the placed “camouflage” will last regardless of the greasy surface, apply powder on top, preferably mineral based.
Avoid touching the place during the day, because you may infect it or spoil the concealing makeup. Applying more than one layer of concealer is also a bad idea, because it will make the affected area prominent and thus more visible.