To prepare, the youth group needs to go to people and businesses collecting donations that may be auctioned off, making it clear what the money collected will be used for. Perhaps there are some businesspeople in the congregation that can donate items or services such as haircuts, daycare, art, etc. The number of different items are endless. Youth may also volunteer items to be auctioned such as 4 hours of babysitting. A group of 3 or 4 boys may volunteer 8 hours of labour to be auctioned. The larger the variety of the items auctioned off, the better.
Designate a night for the social. When I have been involved, it has been held as a valentine event. Charge admission to cover the cost of hors d’ourves or desserts. Arrange for there to be some type of entertainment for the evening, either from the youth and the church or from a college ministry team if you have access to one.
When the people arrive on the night of the auction, have the different items to be auctioned off arranged on tables around the room with a piece of paper accompanying each item for people to write their name and bid on. The bid on each item will rise as people try and outbid each other for the things they want. Set a time for the bidding to end, and at that time, collect all sheets.
Have people take their seats, serve the food/desserts, and announce the winning bidders for each item, interrupting the periods of announcement with whatever entertainment you have planned.
At a church of 200 people with a youth group of 20-30, this event regularly raised between $1,000 and $1,300! If anyone donates a big-ticket item, it may add a nice touch to auction that off at the end. Planning is everything.