How to Throw a Surprise Housewarming Party. Surprise parties are difficult to pull off, but a surprise housewarming party is probably one of the easier ones. Once the people have moved in you, just need to be invited over and you can take it from there. Follow the steps below to throw a successful surprise housewarming party.
Get an invitation to the home of the family that has moved into the new home. Make sure it allows you enough time for the preparations you will have to make for the surprise party.
Send out invitations. Include all the details on the card. You need people to meet at your home and take the whole crew at the same time to the family. You don't want anyone showing up at the people's home without you because this would blow the whole surprise.
Shop for food and anything else you will need for the party. You want to have everything that is needed for a party since the family will not be expecting so many guests.
Put out a sign at your home for any late comers. You want to wait a reasonable amount of time for your guests, but you can't afford to be late for dinner or whatever the family has invited you for.
Lead the caravan to the home where the party is going to be, however don't let everyone park in front of the home. Wait until they get into position--out of sight but close enough to yell surprise when the time is right--and ring the doorbell.
Let the new home owners open the door and try to lure them outside--then yell, "Surprise," and have your camera ready. This is the trickiest part because you want to make sure you have everyone together at the right time.