As far as being mature and asking for outside help, I think a part of being mature is know when and where it is appropriate to ask for help. Kudos.
You may wish to write about what has inspired you to get to the point you are at now, looking to a particular future in which your grad school studies play a stepping stone. WHO has inspired you and why? This can be a convenient framework to include the excellent points Marina mentions. It can be somewhat narrative, so it is interesting for the reader, and provides an opportunity to synthesize your background with your goals. Past, present and future in a tidy package.