Hey WordPress contributors! I want to know what you consider the optimal workflow for contributing to WordPress. Things like trac, diffs, vagrants, grunting, milestones, config, etc. all sound weird and hard. So I have some questions for you answer. I know your answers will help me contribute ten bazillion times more efficiently. The more detailed your answer, the better. (You can even write up a sweet blog post as an answer!)
* What are all the things you use for your local workflow (apps, Vagrant, whatever)?
* What do you use to keep your local install up to date?
* What do you use to create or apply patches?
* Got any tips to make me ultra-efficient?