Invite a good mix of guests.
When wondering how to plan a party, don't overlook the importance of the right guests. If you are inviting friends from a variety of different "groups" of people you know, make sure to pay attention to your guest list. You don't want to invite an incompatible mix of people, practically ensuring an evening filled with boisterous political arguments and grimacing faces.
Keep the menu simple.
It's always tempting to show off with elaborate meals and dishes, but the best casual parties usually feature simple, delicious food. Put out cheese and fruit plates as appetizers and snacks. If you want to grill, select something that can be done ahead of time, such as marinated chicken, so that you can mainly focus on having fun and taking care of your guests. Serve something for dessert like strawberry shortcake, which can be prepped and then assembled in minutes.
Plan one activity that everyone would enjoy.
In case conversation lags, plan at least one activity that everyone might participate in such as a board or lawn game. We love the latest oversized version of popular table games in lawn game form, such as Jenga and Yahtzee. Put on some music in the background and prepare for lots of laughter, as guests tire themselves out rolling giant dice out of a bucket.
Create a comfortable environment.
Especially if your party has more than just a few guests, create little spaces for people to feel comfortable socializing one-on-one, such as patio chairs clustered together in a shaded corner. Also, if the day is really warm, make an extra effort to help cool guests off by plugging in fans, offering plenty of icy drinks, and arranging the party time to coincide with the cooler part of the evening.
Work the room.
Learning how to plan a party is more than just the prep work. The best parties usually involve the host and hostess being at the top of their game during the event. Try to prepare as much as possible ahead of time. For example, don't make every cocktail to order. Rather, have a pitcher of something as well as bottles of beer. This will help refill drinks more efficiently and not keep you tied to the kitchen. Also, watch for guests that aren't masters of small talk (we all get a little shy sometimes) and help them out by introducing them around to your other friends. Essentially, the best hosts are those that plan ahead, make their guests comfortable, and keep the evening fun.