Equally important as the on time payments is the credit line to credit balance ratio.
The best is less than 10% utilization. IE: you have a total of $10,000 in credit lines, your total owed is under $1,000.
If your utilization is great than that, rather than offer a penny to that old TL holder, I'd shove every penny into bringing down my balances.
If you really want to improve your score, then learn what actions will do it best and fastest.
If it's paying down balances, then learn about the snowball method, and use it. Add in the extra cash from everything that you can save on while you're working on getting balances down.
I don't go out for coffee. But if you do, if you are in the habit of stopping and grabbing coffee and a little something on the way to work, just making your coffee at home and skipping the treats will give you a extra couple hundred to throw at the CCs every month.
Most people have a lot of recurring costs that they don't think about, because they've become part of their lives. But cutting them can help if you're trying to knock down credit balances.
A higher deductible on car, home owner or renter's insurance. A lower limit for texts, or data plan for a cell phone.
They can add up.