My little brother who is immortal rank is 12 year old and I am trying to help him go pro or improve his career, what can I do for him?

[Here's the video link if you're lazy to read](https://youtu.be/FPvPhBXxEAM) Peeking is one of the most important skills and it is often overlooked. Everyone talks about aim and crosshair placement, but knowing how to peek properly is what...