Outreach is definitely something that is very specific to each team and its circumstances. That being said, there are some categories that many teams' outreach efforts fall under:
- Demos at community events - drive your robot in a parade, present at your local Maker Faire, present at industry conferences, etc.
- Offseason competitions, though you need to be pretty 'on it' to pull one off successfully. Harder if there are already some events in your area.
- Community service - use your STEM knowledge to benefit your community! We've done some neat stuff with this - check out our website for more info.
- Mentoring other FIRST teams, whether they're JrFLL, FLL, FTC, or rookie FRC teams.
- Hosting a conference for teams to share knowledge - it's a fun way to bring the community together and spread the love. People who know about drivetrains present on drivetrains while learning about scouting methods and LabView - it's a great experience.
That's just what I can think of off the top of my head - there are as many ways to do outreach as there are FRC teams. Look at the websites of successful Chairman's teams, especially Hall of Fame teams, if you're stuck - they know what good outreach is.