What I have learned.

Watch the passives...I heard that a lot
Keep the count down with "was" and "were"

I had to learn to focus on the truth behind the story I wanted to write. If my main character is walking in one scene then in the same scene a few paragraphs later she can't be driving- that's where you exit the true life part and enter the part where I am only concentrating on the big stuff not the small stuff. Still working on it.

Keep the commas to a minimum. I apparently am a Comma Whore- and learning to change.
"Hi my name is Tiffany and I gave out my commas like it was nobody's business. Thank you."

Next is...only let your closest comrads read it, and with that it would also help for it to be people 1) interested in the type of story you're writing & 2) someone else who knows how to tell you how it is and to pay attention to the truth of the story, the passives, and the over usage of commas.

Keep the exclamation count down also!!!!!!!!!!!!!!!!!!!!!! Editors, publishors, and whoever-ors don't like them. So I've heard. I love exclamation points!!!!!!!!!!!!! It means I'm happy!!!!!!!!!!!!!! ;D

On Query letters- 250 words max. Get the agent's last name and Mr. or Mrs. (enter last name)
3 paragraphs. A Hook- get them hooked immediately. Explain the main gist of your story here in no more than 2 sentences. Snazzy catch phrases, your WRITER's VOICE( a term I just learned which means to show off your specific writing talent. Mine tends to be sarcasm, and coming up with random descriptions :P)
A summary- Summarize the book- you have more room here rather than in the hook. Again use your voice. It's not in first person remember that. And try to pick the bigger issues that the character has to face. How do they handle them? What are the consequences?
Then another Hook at the end- What happens to the character as they make their decision? What could be the outcome? Do the whole dum dum dum(scary music playing woman screaming in the background) that type of ending...something to make the person reading this jump out of their seat to email you and ask for more NOW!!
Then a last paragraph to add in your credentials...or if you don't have any like me...then you just let them know the title of your book the genre and how many words and how grateful you are for their time.

Then cross your fingers and toes, carry around your lucky rabbit's foot, and do whatever else you believe will help as you wait. Don't expect an immediate answer- most of them tell you it could be weeks. But also don't do like I did and send out a lot thinking your writing is flawless-- noticed I mentioned finding someone to help edit-- it is a great way to make sure your writing is shining with well done edits thanks to your colleague(which you will take out to eat if you ever get a deal!!). Send out a small amount of query letters 5-10. See what kinda response you get. If it isn't pleasant- like mine- then go back and edit some more find something online like  www.agentqueryconnect.com and find someone to help you some more or google and see what you can find. Then try it again with a new set of agents.

Eventually the harder you try and the more effort you put into editing it will come out flawless, and you will get that deal...just don't rush out -- like I did :D -- take your time. Study the notes on writing and don't expect to get it all done in just a few months. It takes time- lots of it- but I've heard in the end it is most definitely all worth it.
So if you are like me-- then you are willing to take that time to perfect what you do to turn it into a career-- and become the author that you have always wanted to be :D