Ask HN: What are your first steps in setting up a new Mac?

I just got a new Macbook for work, and I'm just wondering what you guys typically do when setting up a brand new computer (when you're not just transferring everything from your old one).

I know my very first step will be to install Mathias's Dotfiles[1], but I'm not sure where to go next. Thoughts?

1. https://github.com/mathiasbynens/dotfiles