If you don't have plans yet, chances are many of your friends don't either, so if you invite people over even with little notice, they'll most likely attend. Many people feel overwhelmed by the pressure to go out and have a blast, but the traffic and jacked up prices at restaurants can deter people from wanting to go out.
Mix 2 cups liquid castile soap with ½ cup warm water. Add ½ cup lemon juice. You can add essential oils if you want. Mix with a whisk, then funnel into a bottle.