If your business requires significant operating capital — for inventory, rent, labor, and such — don’t take it out of the business to pay your personal expenses. Understand that operating money isn’t yours to spend; it’s a vital part of your business. Also, be sure not to spend money you collect from your customers for taxes. That doesn’t belong to you, either; it belongs to the government. You didn’t earn it. You just collected it.
I recall with some dismay a client of my ad agency who appeared to be doing quite well. What I — and others — didn’t realize was that he was collecting hefty state tax payments from his customers, then not reporting them, and not turning the money over to the state. The state tax authority soon caught up with him, and he narrowly escaped going to prison. As the bible says, “Give unto Caesar what is Caesar’s.” Don’t fool with tax people. They’ll destroy you.
Keep your own personal finances in order. Your money problems are almost certain to impact your business. If you have consumer debt, do your best to pay it off — or at least pay it down — before your startup. Take the money out of your savings, if you have to.