The statement character limit is really short so just get straight into talking about what you've learnt from your commitments, challenges you've faced, how you overcame them, skills you've gained, etc. Make sure you link everything to an example of something you've done. Here's something to get started with:
Activities X, X, X have allowed me to improve my X and ability to X through X. Working collaboratively with the community, I have been able to achieve X and X. My efforts in X reinforced to me the importance of X skill to achieve X. Additionally, I've learnt X, utilising this skill/knowledge/lesson to do X successfully.