Out with the old and in with the new.
Old: clean up the negative accounts as best you can. If you can't get them deleted, settling for "IIB" zero balance will suffice. Lenders expect there will be negative items preceding a bankruptcy, so having them removed isn't as big a deal as it would be were there no BK showing. What you want to establish is a pattern of moderate and responsible credit usage after your discharge.
New: Open some new revolving credit. Secured card, starter cards. This is so that you can begin building positive history after discharge. So many folks don't do this and it hurts them- without new, positive history- prospective lenders (and FICO) have nothing but the old stuff and the BK to judge your creditworthiness on. Open some new accounts, keep the balances low and the payments in time- show them that your financial "fresh start" really was a fresh start!
Remember that anything "negative" is even more so with a BK showing. Too many inquiries on your CR hurts, but it's even worse with a BK showing. Same with high utilization. Same with opening too much new credit in a short period of time. Those things set off warning bells- even more so after a recent BK. Do your rebuilding in a paced and methodical manner, not applying for things unless you are reasonably sure you'll be approved, etc. Not opening a bunch of "'rebuilder" cards just because you can. Plan ahead and open just those which benefit you.
Protect yourself from future disaster too.
After BK you can't file again for years, making you a sitting duck for health issues, insurance claims, etc. Make sure you have proper insurance coverage- especially liability. Get the best health insurance you can + disability coverage if appropriate. Keep an emergency savings fund to smooth out the financial ripples that come along.
