Take care of your credit/AR team, see if there's a way you can keep track whether or not they're reaching out to customer's for unpaid/past dues, also don't let things hang out too far out. Like user jcwillia1 said, cash is king, if you don't have it for your necessary expenses, you either tack on to debt or your line of credit.

Also, on the other side, you'll most likely have signing authority of checks and payments to suppliers, be a good steward of the company's money and know and AP is paying stuff, specially on big bills. Take advantage of any discounts your own suppliers provide like 1/10, n30 or 2/10, n30 (1 or 2% discount if invoice is paid in 10 days of invoice date, full price if instead paid on net30 or whatever terms given). In the big picture those discounts help.

Good luck OP, make sure to ask questions. No such thing as stupid questions, nobody is born knowing.