How to Run a Successful Instagram Contest or Giveaway : Social Media Examiner
Disclose All Terms and Conditions of the Contest
Third, you must fully disclose the terms and conditions of the contest. This can include defining criteria like:
Make sure you’ve decided on these factors before you’re ready to launch your contest. The length of the contest will determine how many times you want to post about it.
Other Considerations
Also familiarize yourself with your local, state, provincial, and federal regulations when it comes to contests, giveaways, and sweepstakes. You don’t want to violate any of those laws either.
Also be sure to use the right terminology when you run your contest: