I'm not a TV writer either (I do features), so take this for what it's worth. There's a great book on writing treatments for both features and television. It's called Writing Treatments That Sell
by Atchity and Wong.
There's an entire section on creating and marketing television premises.
Your best tool will be what's called a "show bible", which will consist of the following (taken from the above-mentioned book)
- a one-page overview of the pilot
- a one-page description of all the major characters
- extended description of each character
- a one-page description of the franchise or setting
- "background" on the series concept, where appropriate
- the pilot treatment
- a brief description of from four to twelve future episodes
Basically, unless you write the pilot and most of the first season into scripts that blow
people away (and even if you do), you'll most likely be paired with a "show runner" (an experienced creator of past television shows) who can guide you and keep the show on track.
Then, ideally, you learn the ropes and someday be your own show runner, or get brought on as a show runner for some other "rookie's" great idea.
Good luck to you. And again, I highly recommend that book!