How do you use the BRRR method to pay off a home?

[Mike Brown]

For example, say you buy an $80k home with $20k down and spend $15k in renos. It goes up to $125k after a year of "seasoning", which is an increase of $45k. In newbie terms, what is the process of using that $45k increase to pay down the original mortgage balance? The reason I want to do this is so I can get higher cash flow from the properties.