However, since no one is perfect, you only get 25 total points to fill the levels with. That means that you'll have to scatter those 25 points over 5 categories. Personality traits affect how quickly you fulfill your needs, how you acquire skills for job promotion and how easy it is to make friends. Toggle the levels up and down by clicking the mouse to the right of a trait to increase and to the left to decrease. Giving your Sim a reasonable amount of neatness will make the game easier, because you won't have to constantly be running around cleaning up messes.
Neat roommates tend to get along better with others as well.
Neat Sims are likelier to wash up after eating meals and using the bathroom. Messy Sims are likelier to leave a mess after a shower, or throw their plate on the floor after eating a meal. Outgoing This meter determines how friendly your Sim is toward others. A high rating will produce a real social butterfly. This is a good thing to have if pursuing careers in Politics, Sports or Entertainment.