Deeper Characters Guide
From me to you, in hopes that you all might find this useful someday when searching through these boards for some obscure post.
Guide to Better Rounded Characters
1) Pick 2-3 Major Goals for your character. These can be sequential such as getting your diploma/degree in something and becoming a recognized go-to person in that particular field.
2) Pick 1-3 Advantages of your character. Maybe they're really smart? Maybe they have good coordination? Maybe they're a people person and can usually joke their way out of bad situations? Whatever it is, just remember that if you decide to pick that your character is really strong or really fast or really smart... Realize one thing, there is *ALWAYS* someone better than you are. Especially if you are starting out at level 10 :)
3) In line with the last step. Pick 1-3 Flaws for your character. Remember some things that may seem advantageous are often not so. Things like codes of honor and always tellign the truth (or on the flip side compulsive lying). In addition to the usual flaws you might expect someone to have RL... Being poor or in debt, having a criminal record, having a drug habit, ect...
NOTE: The general idea here is to try and keep your character 'balanced' atleast to start or even stack the deck against them. A character that has to overcome many obstacles on their way to achieving their goals usually has a much more interesting story to tell when it is all over (or along the way) than a character who is pristine and perfect out of the starting gates so to speak.
4) Skills skills skills, a character is nothing if they can do everything. Pick 1-2 skills you excel in, pick 2-4 skills you are good in, pick 2-4 skills you are hopeless in, pick 1-2 skills you simply cant do anything right in.
5) Attitude - Using the information above, figuring out an attitude should be relatively easy. If you have lots of social graces then obviously you'll probably have a more outgoing personality than someone who has a whole bunch of scientific and computer skills and sits at their computer all day playing video games (we don't know anyone like that do we?). Needless to say your background which comes next should fit and describe your attitude.
6) Background - Often refered to as a game of 20 questions (or more!). How do you introduce yourself? Who are your parents? What is their statuses? Do you have any siblings? What are their statuses? Do you have any other family you are/were close to like cousins, uncles, grandparents? Do they have any childhood friends? Are they still friends? How was their childhood was it carefree and innocent or were they forced to get a job at the age of 10 in a sweat shop making Nike shoes at 500 yen an hour to support an ailing parent? What was their dream job? What are they doing now? Why are they doing it? If they are in highschool where do they intend to go? If they are in college what do they intend to be? For the characters who are older (cronologically) what have you been doing with your life? How long have you been working? Have you been working for one company loyally or have you been drifting around? Are they putting their advantages/skills to good use? Are they in a position where they can accomplish their goals? Ect...
NOTE: Keep in mind that not all of these may be applicable and not all possible questions are covered but these should give you a good idea of where to start and what to ask to end up with a decent background that's probably a lot longer than you expected when starting this out.