You don't need a credit overhaul to strengthen your position before applying for a mortgage — a handful of specific, disciplined habits, kept up over a few months, tend to matter more than any one dramatic move.
Paying every bill on time, every time, is the single highest-leverage habit, since payment history is the largest ingredient in most credit scores. If you've ever missed a payment, setting up autopay or calendar reminders for the months leading up to your mortgage application is one of the simplest things you can do.
Credit utilization — how much of your available credit you're actively using — is the next biggest lever. Generally, keeping balances well below your credit limits, on each card individually and across all your cards combined, tends to help more than it hurts to pay a card off entirely and close it. In fact, closing an account you've had for years can shorten your credit history and sometimes work against you, so paying down balances is usually the better move over closing accounts outright.
It's also worth being cautious about opening new credit accounts in the months before you apply for a mortgage — each new account and each hard inquiry can have a temporary effect, and lenders may ask about any new account that shows up mid-process. The same caution applies to large new purchases on credit, like furniture or a car, even after you're pre-approved: lenders often re-check credit close to closing, and new debt can change your debt-to-income ratio enough to affect your approval.
None of these moves work overnight — credit habits compound over months, not days. That's exactly why the Prepare stage exists before Finance and Offer: giving yourself lead time to build a stronger file is one of the few parts of this process that's fully within your control.