Even within Ocean County, it will vary by location. There ae specific complexes or developments that have better turnouts on Sat vs. Sun. Overall, if I had to pick one, I would probably say that county wide, Sunday produces more OH visitors.
Over the years, I have held OH's that have yielded no visitors, and I have been overwhelmed with more than 30 visitors. Many visitors are not serious buyers, but some are.
If your community allows directionals, make extensive use of those. Place the directional signs just prior to the OH, and remove them promptly after. Do check with your municipality for rules governing sign placement. In some towns, none are permitted. Other towns require signs be placed only on private property and with the permission of that property owner. Other towns allow signs on street corners, sidewalks, and street medians, but have time limits. Observe the rules, as the fines can be hefty, and your signs may also disappear.
Post your open house on many websites to increase your turnout. The only time we use classified ads in the newspaper is for open houses. Even with this, few of the visitors indicate the paper as their source. We still include that in the promotion of the open house.
If you can, do both Sat and Sunday.