Some work and some do not. Diet generally does not affect acne. Scientific studies show that ultraviolet light does not help acne. Self treatment by expressing lesions, etc. There are some procedures physicians can do when indicated.
Many people find that hypoallergenic, water based cosmetics are helpful.
Keep your skin clean. Wash twice daily. Too much scrubbing makes acne worse. Most acne will respond adequately to topical therapy, often to those preparations available over the counter. Most people don't give these drugs an adequate trial.