A Labor Day party involving strictly adults can be a great time to relax and unwind. For this party, you can bring out the different forms of mixed alcohol drinks. Most people only know a few drink mixes. Have fun and experiment with different concoctions or have a professional there to teach about them.
This Labor Day turn on the sprinkler and sip some lemonade, but don't forget to give a toast to those who made it possible.  Without them, there would be no standard of 8 hour workdays and minimum wage!
Party Games