After reading your profile, I see that you have been in Real Estate for 16 years. That's great.
Over the past several months, I have hosted several open houses on my listings, and I have had a great response when I put signs out a week early and send out flyers to the neighborhood inviting them to the open house. Our MLS has an option to include our open house dates so that buyers searching on the public MLS sees it.
Some other pointers: if you don't have listings, host an OH for another agent within your company, if you don't want to spend the money to mail out invitations to your open house, walk the neighborhood and put them in mailboxes. Also, be aware, when placing OH signs out a week early you may lose some. We've had several kids take them...but, for the most part, they've remained where placed and have driven traffic to the OH. Hope that helps some--it has helped me.