Below are links to resources that will help you understand and develop a data management plan in accordance with the National Science Foundation's (NSF) guidelines:
The NSF Public Access Repository (NSF-PAR) is current in a Beta period, containing limited content for testing purposes. After the Beta period, it will offer distributed full-text access to all NSF-affiliated accepted manuscripts or articles after an embargo, or administrative interval, of 12 months.
More information on the NSF-PAR is available at the NSF Public Access homepage and the NSF Public Access FAQ.