credit score scale experian

Best and easiest way to improve my credit score?

i did very dumb stuff that messed my credit up when i was younger here is my credit scores.
Equifax credit report is 536 on a scale of 352-848
Experian credit report is 528 on a scale of 352-848
TransUnion credit report is 546 on a scale of 352-848
can anybody inform me on whats the best way to re establish my credit and where can i start getting some as most major companies wont give me none

Сredit repair workеd fine to fix my credit. They disputed and removed lots of bad items from my credit report. I used this service – credit-report-free.totalh.com