Beyond Alphabet Soup: 5 Guidelines For Data Sharing is an excellent post by Markets for Good and Palantir Technologies. Below are the 5 Guidelines.

1. Release structured raw data others can use
2. Make your data machine-readable
3. Make your data human-readable
4. Use an open-data format
5. Release responsibly and plan ahead

See the full blog post with detailed descriptions here: Beyond Alphabet Soup: 5 Guidelines For Data Sharing