Don't go overboard, try the following. Get a new unopened tube of tretinoin (very important, i've wasted months trying to figure out why it didnt work doing gay skincare routine twice a day and nothing worked it just got worse. I've ruled out everything else, and the same tube worked well a year ago, so it's likely that it lost its efficacy).
Use a gentle moisturizing cleanser first. Then wait a few minutes for it to try. Then apply the tretinoin. Then wait about 20 minutes and apply the moisturizer (I am using cerave facial moisturizer with niacimide). Every two days in the evening. If you're going outside in the sun you need to wear sunscreen otherwise the tretinoin gets destroyed. The moisturizer I'm using is availabe with built in sunscreen, so it saves me some time. That's all there is to it. Diet makes a difference, but even with a bad diet the tretinoin will still work.