A lot of people are going to recommend a rave, but I will not.
Your first experience should be in a place you are very comfortable, at home with a few friends, maybe at a house party as long as its calm and not too rowdy. The high school drinking parties are usually a shitty place to roll lol, no one likes a drunk fucker when their rolling
Before you roll though, check your pills on
www.pillreports.com there are a lot of really shitty pills being sold as MDMA. Most are horrible, piperazines, meth, you name it... drink a good amount of water (not too much!) and just take it easy, its always best to get to know a drug before you go out and do it around hundreds of people