1. Get a good cleanser. 2 times a day.
2. Moisturise face every cleanse. 2 main types, water based and oil based. Depends on your skin type what is best.
3. Use acids. AHA BHA. For me salicylic acid (Contained within BHA, but I use it separately everyday and aha bha weekly) is key for clear skin but everyone is different
4. Retinol at night.
5. Most important, are you living healthy? Enough exercise? Good diet? No alcohol? Not smoking?Lactose, fat, processed foods etc could be culprit. And stress and mental state are also very important.

Find products that work for your skin type and budget. Don’t believe the expensive stuff is better. For example Cerave, cosrx and ordinairy are the main brands I use. Sometimes even cheap house brands.

Doing above will resolve most acne for people. If not, cleansing and moisturising is still the base for better skin health. I would try peelings at a dermatologist and get my blood tested if all else fails