The usual ways including direction signs with balloons, with yard sign with more balloons. Craigslist, and the local paper may have a section dedicated for open house ads, or even just in the classified section. If you are on Zillow, you can post an open house there as well. Even here on Trulia you can post an ad in the blog section. Good luck and since you are a FSBO, you may be interested in the blog attached to the link below.
After doing open houses for may years and spending a considerable amount of money on these activities, talking to people that attend them about how they heard about the open house, it bacame clear that a very small fraction of those that attend, do so as a direct result of the event being advertised.
The majority of open houses that are held are unadvertised......advertising is done mainly for the owner, that thinks it makes a difference. Our recommendation is to put out several signs and forget about advertising it...save the money .
Atlanta Real Estate Agent
Keller Williams Realty Consultants