This is a hard question for someone who has never hosted a bachelorette party, but I'll give it my best go. As many wise ladies have said before me, make sure that the party you plan will bless the bride-to-be. The whole point of this time is to have fun with her before her big day.
If she's outdoorsy, go on a hike or to the zoo. If she's into sports, attend a sporting event or play a game of...whatever. If she's into beauty treatments, plan a spa day.
What is the bride's love language? If her "love tank" is filled with gifts, ask each guest to bring a small gift for the bride. If the bride loves words of affirmation, ask everyone to write a note to the bride. I'm sure you get the idea :)