How To Raise My Credit Score Quickly? No Credit Card Debt, Just Collections?

So, I have a credit score of 570 and I’d like to get to 650 as quick as possible. I have 4 satisfactory loans (all student) and 6 negative collections (medical bills, old cell phone bills, etc) that roughly equal $1400 dollars. None of them are credit cards/I’ve never had a credit card.
I know and want to pay off the $1400 but I keep reading that paying off old debts will show activity and lower your score? Some people say that I should start by getting a secured credit card and be diligent about paying it on time to start some new, good credit then pay off old debts?
What’s your suggestion?