bad credit truck financing

I tried to build credit so i finance a car now its been reposed and my credit has suffered,how can i rebuild?

WHENI STARTED MY CREDIT WAS 691 NOW IT 520
I HAVE A FEW OTHER MINOR THINGS ON MY CREDIT BUT THOSE I CAN PAY BACK. THE TRUCK THAT I HAD FINANCED WAS IN A REALLY BAD ACCIDENT AND DIDNT RUN, WILL THE FINANCE COMPANY WANT MONEY FOR REPAIR AS WELL
PLEASE HELP TO LET ME KNOW WHAT I CAN DO TO BRING UP MY CREDIT SCORE.
ALL ANSWER ARE GREATLY APPRECIATED.

the insurance company should cover the accident and pay off any liens on it if it is unrepairable. your credit shouldnt suffer, only your insurance rate. pay off any owing debts and your credit score will go up. dont get any store credit cards (consumer cards) as they are really bad for the credit. as well dont keep checking your credit score, that lowers it significantly! Good luck:)