PartiesParties return to The Sims 2 with a few new twists. Now, instead of just attempting to entertain all of your guests, you'll have to ensure that they have a fun time socializing with each other in order to obtain a good party score. That's right, parties are now ranked based on their success!
In order to throw a party, you'll have to use the phone to initiate one. You'll be able to invite a few Sims over; the higher your relationship score with a Sim, the more likely they are to appear. As the guests arrive, you'll need to start working on their Moods.
All Sims will appear on your lot with a low Hunger score, so the absolute first thing you need to worry about is making some Food. If you have a household Sim with a high Cooking skill, get him or her to start Serving the best dish that they can make well, preferably two or three batches if you have room for all of the plates and enough seating to ensure that everyone can eat comfortably. (If needed, you can buy extra countertops, chairs, or dining tables explicitly for the party, then sell them back afterwards. You won't lose any depreciation money if you sell them the same day you buy them.) If you can, get this started before you call to start the party. Most food will last for six hours, while a party will only last five, so you don't have to worry about spoilage.
After they stuff their faces, your guests will probably want to move on to their Bladder. Since you'll have as many as eight people at a party, depending on your computer's specs, you'll definitely need to have at least two easily-accessible bathrooms near the kitchen; you don't want your guests walking all over the house in order to find a toilet. Again, small bathrooms are easily constructed for party purposes, then sold again afterwards, if they're unnecessary for the day-to-day needs of the household. All you need is a 2x1 slot with a toilet! Just make sure that you have a couple of sinks around for your guests to wash up with.
After these rudimentary Needs are taken care of, it'll be time to move on to the core of a party: Fun and Socializing. You'll have noticed by this time the large Party window in the upper-right corner of the screen; this will indicate how much longer the party will last and how successful it is at the moment you check. Parties are given a textual rank, from the worst (A Total Disaster) to best (A Roof-Raiser). This score is based by taking the amount of Daily relationship points that each guest or household member has gained, adding all of them up, and then dividing them by the number of people on the lot. So, in order for a party to succeed, you'll need to ensure that everyone on the lot is partaking in positive socialization!
(In addition to Fun, Social, Bladder, and Hunger, your guests will also want to increase their Comfort and Energy. The former is easily taken care of with decent seating; the second can only be helped with servings of Coffee or Espresso. You can socialize by talking while you drink or eat, so be sure to get some nice, comfy chairs for this purpose.)
One of the easiest way to do this is to have all of the Sims under your control move towards a Stereo and start dancing, then Calling Over all of your guests, one by one. Dancing with Sims gives you a good amount of relationship points, while also providing Fun, which should encourage your Sims to keep dancing even longer. Not all Sims will enjoy dancing, though, so you'll also want to have a nice television turned on, or perhaps a game machine, so that the Lazier Sims can do something that they enjoy as well. If you notice your guests wandering off in search of their own Fun, be sure to have one of your household Sims tag along and join them in whatever they do; it doesn't matter if your guests are in a great mood, if they're not socializing with anyone! Note that your guests cannot turn on stereos or televisions; if they want to watch TV, you'll have to turn one on for them ahead of time.
Besides gaining a lot of relationship points, you should also be sure not to let your Sims lose massive amounts of them. This most often occurs when Sims witness one of their lovers getting romantically involved with someone else, so you'll have to be careful that this doesn't occur. Dancing is a fairly safe activity that doesn't involve any jealousy penalties, but you'll have to be careful that your Sims don't attempt any autonomous actions that might spark a fight. While lover's spats might make for memorable parties, they won't be very successful in most cases. On the other extreme, you'll need to prevent Sims with mutual Daily Relationships of 100 from socializing too much; they might be successful with every interaction, but this won't help your party score at all.
At the end of the five-hour party, you'll receive a ranking. This doesn't have any effect on anything, unless your Sim had a Want or Fear based on it. Family Sims often want their children to have good parties, while Popular Sims want to throw highly successful parties for their own selfish reasons.