First off super happy that everyone enjoys the sweeter and thanks for all the questions and comments you guys rock!
Answers:
What stitch pattern did you use?
What stitch is it?
The stitch is called a Key Tab Stitch I found it in "basic crochet stitches" by Erika Knight. If you can't find the book just ask and I'll try and make you a video or something. As far as fancy stitches go it is pretty simple to do!
That IS GORGEOUS!!!! And it's your first??!?!?! WOW! Man seeing stuff likes this makes me really wish I know how to knit or crochet.
I am super pumped about your enthusiasm!!!! You should join the awesome crocheting hysteria! This is my first sweeter but I have been I have made quite a few hats (which could be an excellent first project for you!) and such.
Is it all one piece or is it seamed? What weight of yarn/hook size did you use?
It's all one piece, yay no seams! I used this yarn
http://www.naturallycaron.com/shade_cards/country_sh.html it is awesome and I got it on sale! I am kind of a ghetto hobo crocheter when it comes to the finer points of jargin but I think the yarn is 3 oz / 85 g and the hook is E. hope this helps!
How long did it take?!
I can never sleep without finishing whatever I'm crocheting. I must be crazy.
Well I started the bad boy at the end of january and the preceded to not look at it till this week. But if you combine the time of actual crocheting it is probably something like a week and a half of intense crocheting glory. Sadly I don't think you could do it in one night unless you have some super skills hidden in your back pocket so I say try it anyways!
If you would be willing to write up a pattern I think myself and others would be interested!

Sadly my pattern writing skills are a little sketchy and not quite up to par but as a consolation I made this ghetto pattern that is more of a guideline type thing. it may be easier to see if you print it out!

Hope it helps! If you have any questions about it I'll be sure to try and do some problem solving!
HOW'D YOU DO THAT!???!?!?! It's absolutely adorable. *drool*
We call it mad skills.... and far to much free time....
So, if you had no pattern, is there a trick to it? Any tips for someone else wanting to partake in a similar activity?
Well first off I just wrote up a ghetto pattern so that is a good place to start. Some of my little tips of wisdom for free handing it are the following:
1. Find a piece of clothing you already like and look at it for ideas.
2. Get more yarn than you think you will need. It is always better to have a matching hat than half a sleeve.
3. Don't be afraid to take the thing apart if it does not look right. I could have made 2 sweaters in the time it took me to make this one cause I kept refining the sweater
4. Buy nice yarn. I know I hate shelling out the cash but if you don't like the yarn you won't want to wear it.
5. Do your research: even if you don't have a pattern you can find inspiration by looking at other sweaters you like. Also look up new stitches; they can really make something look unique. I like the book " Basic Crochet Stitches" by Erika Knight but there are tones on the internet too!
Thanks for taking an interest! I am a really big fan of patternless creations and I bet you can bust out something fabulous as well!
Thanks everyone again! Feel free to ask more questions and of course comment and recommend this to others!