Pick a public spot to write. Diablo Cody does all of her writing in public, where she likes to "sit around, eavesdrop, listen to people and watch them." This helps her to come up with the believable dialog she's known for.
Blog it and they will come. Cody initially got her writing practice and exposure through blogs she started in her early twenties, such as "Red Secretary," "Darling Girl," "**** Ranch" and "Girls, Cars and Surfing." Cody's future manager, Mason Novick stumbled upon one of her blogs while surfing the Internet. The professional partnership turned out to be the catalyst for both Cody's published book of memoirs and the script for "Juno."
Create your screenplay without any assurance you'll get paid. Cody wrote the script for "Juno" on spec, which means she wasn't hired or commissioned to write it by a production company. Although Cody wrote the script at the suggestion of manager and future "Juno producer" Mason Novick, she didn't receive any money upfront and risked receiving none at all.
Write a script that can be produced on a low budget. Cody's script for "Juno" took place in a nondescript small town in the US and required no special effects or elaborate costuming, which made it more appealing to movie makers from a budgetary standpoint. Cody says that the reaction she received from producers was "let's make it. It isn't gonna cost much."