I was thinking of buying a nice cake stand for a sweet sixteen cake I have to make next month. I want it back. How do I get it back? Do I charge her for it? Do I get it from the restaurant? Never had to do this before.

You charge a refundable deposit that equals the cost of the stand. If they do not return it, you keep the deposit and buy a new one.

Usually I have the client return it by a certain date

Yes, charge a deposit, and if they pay for it with a check, cash the check abd just hold the cash. When the stand is returned - complete and not broken, they get the money back. Make sure you check it when it is returned. I didn't once, and regretted it - a major part of the stand was gone. (and I had already given their deposit back)