Inviting the right group of people is first and foremost on the list. Make sure you invite people of like minds per party.  And don't invite more then you think you can handle for one dinner party. Keep it down to 10 or 12 or less or you will be frazzled by the night's end. Keep the menu simple unless you plan to have it catered or have kitchen help. You are going to be tense enough worrying that everything is perfect, so don't over-do the menu.

Plan fun activities, such as pictionary, trivial pursuit, card games, (Bridge, Gin Rummy, even UNO can be fun with the right group of people.) charades, sing-a-longs, even karaoke can be fun after everyone has had a few cocktails.

Keep the conversation light and steer away from anything that could cause argumentative debates.

And most importantly have a good time. Take pictures and videos, they will one day become cherished memories that you WILL cherish for a lifetime.