One of the best ways to find out if you’re running a successful event is to listen to your event attendees. The good news is that social media makes it easier than ever to “eavesdrop” on what your attendees are saying — while the event is taking place. And you won’t need to get a court order to do any of it.

With the right amount of planning you can make sure you’re doing a great job and head off any potential problems before they get out of hand.

Let’s take a look at 8 ways you can eavesdrop while creating an atmosphere of open sharing. This will allow you to ramp up engagement and gather some instant feedback during your event.

1. Be sure attendees can check in: Set up a Foursquare venue for your event if it doesn’t exist already, and let your attendees know. This allows you and your attendees to “check in” and see who else is already at the event. You can create tips and to-dos for attendees too. But also keep an eye out for comments, tips, and to-dos from your attendees.

2. Encourage attendees to post photos to Facebook: Allow attendees to post pictures to your Page’s wall during the event. Invite attendees to tag themselves and their friends. You’ll get some great shots of what people are enjoying about your event.

3. Create a unique Twitter hashtag for the event: Make sure everyone knows the hashtag by placing it on invites, registration forms, and on signs throughout the venue. Then encourage attendees to use it whenever they tweet about your event. This allows you to search for the hashtag and follow the conversation all in one place. (You can monitor all the tweets by using a service like Hootsuite.)

4. Collect the Twitter handles of your attendees: Make this part of the registration process so you can create a Twitter list of event attendees which you can monitor during the event. Also, use attendees’ Twitter handles on name tags to encourage people to connect and gab about the event.

5. Set up searches for the event and keywords: Some people may not use the official hashtag to talk about your event. Be sure to set up Google Alerts and Twitter searches to catch those straggling comments.

6. Set up a QR code to a short survey at the event: Hang QR codes around the event venue to get feedback while it’s still fresh in your attendees’ minds.

7. Conduct a Pre-Event Survey: Find out what your attendees are expecting from your event. This helps you plan accordingly and gauge how well you’ve done at meeting those expectations.

8. Say “thank you”: When you can, be sure to thank attendees who posted to social media about the event. This could spur more feedback you wouldn’t have gotten otherwise.

By using the suggestions above to eavesdrop on your attendees you’ll be able to better gauge how well you did at meeting their expectations. You’ll also find out what areas you may need to adjust for your next event.

And the good news is you found out all this great feedback without having to violate anyone’s privacy. Hooray!

What are some of the ways you listen to your event attendees during the event? Share your thoughts with us in the comments below.