After performing 450+ weddings I have had the opportunity to see what works and what doesn't work to help make your wedding reception the party you have dreamt of. Some of these may seem a little obvious but I feel like a couple of these are not commonly thought of or discussed.
Invite fun people! - Seems obvious but when your wedding guest list is 200 and 150 of these are your parents' friends and their coworkers, you are less likely to have a party. The majority of your guests will end up leaving early and now your dance floor and party look very small. Make sure to invite as many of your friends as possible and limit your parents invites, if possible.
Create a fun dinner atmosphere - I firmly believe that dinner is the gateway to the party. When I work with couples I am up front in sharing that dinner music sets the stage for the party. Far too often couples want dinner music to be slow, background music when their guests are eating. Problem with that is eating a big meal and listening to slow music puts people to sleep. It becomes even harder to get the dance floor going once dinner has wrapped up. I play fun, upbeat music that keeps the energy up during dinner for this reason. This is a great place to add games or activities like the Shoe Game, Photodash or similar to create an energetic atmosphere.
Skip the "Fake Exit" - The "fake exit" is when your guests line up outside, or wherever send off occurs, and you and your spouse make you way out among your guests pretending to leave. Afterwards you and your guests are expected to go back into the reception to continue the party. More often than not, your guests will use this time as a reason to head out to their car. Sometimes the reason for doing a "fake exit" is the desire to allow older family members the opportunity to take part in the send off. Another reason could be your photographer's coverage ends an hour or more before your reception is scheduled to end and they want to ensure that you have coverage of your send off. I would suggest paying whatever the fee is for your photographer to hang out one more hour and not kill your party. (Side note - I often advertise this as a photo op when a "fake exit" is on the timeline. It doesn't always work but it's better than explaining to your guests that you are leaving but not leaving.)
It's your party...DANCE! - Your wedding day is a great time to visit with your guests and catch up with family/friends you haven't seen in some time. However when your dance floor opens and you and your spouse are not on the dancefloor that tells your guests that the party isn't important to you. Find time in the timeline to go to each table and visit with your guests during dinner. Your planner can assist in making this happen. The moment your dancefloor opens, you and your friends will be ready to dance!