Use Facebook to organize online versions of events and contests you ordinarily hold in-person, such as a raffle. Create a Facebook event and provide numbers to each person who RSVPs, using the raffle as an incentive for more people to RSVP to the event. Then, use an online integer generator to draw the winning number online and use the Facebook events group messaging feature to announce the winner via a group message.
Sign in to your Facebook account. Choose "Events" from under your name, then click "Create an Event."
Input the desired date and time of the raffle drawing, a name for the raffle and a description of what the person who wins receives as a prize. Choose "Select Guests," click the name or profile picture of each person you want to invite, then select "Save and Close." Untick the box next to "Anyone Can View and RSVP" if you don't want the event to be public, then click "Create Event."
Check your RSVPs each day and send an individual message to each user who RSVPs giving him a random raffle number. The easiest way to do this is in sequence -- the first person who responds gets "1," and so forth. Continue issuing raffle numbers until the date and time of the raffle.
Use an "integer generator" -- Random.org and the website for the University of Illinois at Chicago have them -- to pick your raffle number. Input "1" in the "Number of Integers" field, "1" in the "Between" field and the total number of participants in the "And" field. Click the "Get Numbers" button to generate the winning raffle number.
Click "Message All Guests" along the left side of the event page. Send out a message, including the winning raffle number and instructions as to how the winner can claim his prize.