Was just wondering how to get my credit score back up
Applying for a secured or prepaid credit card may help with your score. I also check Credit Sesame and Credit Karma regularly to review my score, but I would look into applying for a secured or prepaid card and making small purchases monthly and then paying off those charges. I don't know too much about it, but you may also want to look into Experian Boost. Good luck!
Depends on your situation. But general guidelines are keep utilization below 30%, keep longest card or account open, pay all bills on time.