The California Digital Library has created a free, open-source resource called DMPTools to guide researchers through the process of creating a data management plan, whether as part of a funding requirement or for their own benefit. The brief video above describes the DMPtool.
DMPTool is an excellent place to start. This comprehensive, easy-to-use, open-source tool guides you through a developing a data management plan tailored to your needs that you can easily export. You'll create an ID and password, so your plan will stay private. Step by step instructions let you target your plan for a particular granting body. You can also browse an index page with sample plans, templates, and guidance.
This Primer on Data Management [PDF] from DataOne covers the basics of data management, best practices, and how to consider data management in the larger scheme of your research.