Three areas of focus:
a. This is your big chance, so use it wisely. Reflect on positive moments, jobs, life experiences that relate to your personal employment focus
b. Employers want to know where you have been and where you are going
c. Some personal (not too personal) information is fine, but this is NOT a counselling session
d. They want to know what you do in your spare time, interests, etc. (be careful)
e. They are interested in knowing if you are a healthy, balanced individual, with various interests
Do not go on and on ad nauseam about either trait. Inform the employer that some weaknesses can covert to strengths, and you are currently working on some of your weaknesses-they are not a barrier. You can choose a strength that becomes a weakness if you let it get out of control (i.e. being a perfectionist) and explain what you do to keep it in check. Or, you can choose a relatively unimportant, non-job-related skill that needs improvement (improving skills with spreadsheets) & explain how you are accomplishing that.
The employer wants to know how focused you are for your personal future; what your future aspirations are, how you intend to arrive there.
This could be academic, vocational, or slightly personal. Incorporate some job focus
Always concentrate on your strengths, transferable skills, hard-working attitude and team player capabilities