You use your hard work earning for it. And you underperform in your games, people know that. They will report you and eventually you will be back to your real rank.
Why you do that? C’mon I know you guys are lurking here. Tell me the answer I’m just curious.
I did boost my account with my allowance when I was a teen - around 7-8 years ago, because my friends made fun of me for my low mmr.
I actually calibrated in school with my laptop in front of my friends. It was quite embarrassing moment when I got 400 mmr lmao.