A "proper" development environment

I've got some thoughts on how to manage volunteers who write programs/do systems for your non-profit floating around, but I'm going to write something about a "proper" dev environment first.

Writing programs is not like doing things the proper way. I'm assuming you've written some sort of script/program/macro to help you in your job, and you work in a small organisation (probably non-profit/charity), and there's no software development structure in place. You have this nagging feeling that there's something else you ought to do. You're right. I think the priority for those things you need to do are:

1. Document - What does it do? What does it use? How does it work? What things are you most likely to want to change in future and how do you change them?
2. Test - How do you test it without running the real thing? How do you make it easy to test everything and check that your latest change didn't break anything? How do you test it (see 1)?
3. Deployment - How do you move the thing from where you test it to where it runs for real?
4. Version control - What's the history of changes?