If you're an emotional player, please read this!
The #1 thing you need to keep in mind is "stay positive". As an emotional player, I know that when I'm not feeling good or positive, I perform worse. I tend to tilt more easily and I become less confident in my decision-making and plays. If you know you're not feeling good or positive, take a break from league and do something else. Resetting your mentality and maintaining that positive mindset is key to your success, especially in ranked.