What are you doing now to advertise?
As the PP said, talk to everyone, whether you know them or not, and mention your daycare. As your family, your friends, anyone you can think of to do the same.
I would consider sending out a targeted postcard mailer in your area where mostly families live. It's something you could prepare yourself and fairly inexpensive to mail.
Where I am there are a couple of large companies that have their own internal referal services, but you have to either have your name entered on it by a company employee or call the HR department and ask to be listed. I get calls every week from these two companies without ever having lifted a finger.
I once saw a basket of sugar free suckers at my dentist's office with a business card attached by ribbon to each one. I thought that was creative. You could see if some doctors, dentists, the bank, etc. would allow you to put something like that out.
I'm sure others will have some good suggestions, too.
Chin up, it will pick up soon
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