Even if they know "buy low, sell high", most entrepreneurs don't know the next two things in that sentence.

Something I learned a few years ago that will help most entrepreneurs is working capital management. And that means adding two more phrases to that list: "collect early, pay late".

Collecting early and paying later reduces the cash trapped in your business, cash that you have to find or finance. Simply collecting from customers early and stretching your payables literally unlocks cold hard cash.

I was recently looking at buying a company that had about $50m in working capital. They were extending 140 days to customers but paying on 30 on the nail to suppliers. Competitors were balanced at about 90/90 - collecting 50 days earlier and paying 60 days later. We calculated that we could have literally paid for the company just by rebalancing that situation to match the competitor, releasing tens of millions in cash to allow us to pay off the note very rapidly.

If your business is trading well but struggling for cash, look hard at your receivables and payables, and figure out if you can collect earlier or pay later. You may be surprised at the impact.

You can also look at inventories, but that is another story.