Brush brush brush. And floss. Every day. Every night. Quality toothpaste like Crest Plus. Don’t eat too many sweets. NEVER use meth or coke or heroin. Take your kids to the dentist regularly. Flouride. Don’t do unnecessary potentially grill damaging shit. Wear a mouthguard in football, bball & skateboarding. Don’t bite your fingernails. Don’t chew ice. Please.
Being rude to people in service positions. I went on a date with a man that I thought was entirely out of my league but then he was really rude to the waitress. By the time dinner was over I was no longer flattered and no longer found him at all attractive.