Documentation ensures your data can be discovered and understood by others, as well as by your future self. It is important to document how data was created, derived, or processed, and for what purposes; and also to describe what data mean, their content and structure, and any manipulations that have taken place.
Version control (or version management) refers to handling multiple revisions to files, documents, or data sets, in order to track changes and distinguish one version from another.
Consider keeping master files and milestone versions, and developing an identification system for working copies of files created for specific purposes or people.
Develop a file naming system with brief but meaningful names, and use it consistently. Also consider how to structure multiple files into named folders.
Use durable, standard file formats which are easier to convert, transfer, and preserve. If possible, have data in open, widely available formats that don't require proprietary software to interpret. (NB: If your data will be deposited in an archive, specific file formats might be required.)
Metadata facilitates the searching, retrieving, and analysis of data - it is data that describes other data (so, information about your data).