I set the key-repeat setting for my Mac very, very fast.
I use Dash's text expander functionality all the time - particularly when answering emails.
I create tasks for everything. My life doesn't work without them. Maybe it's because I'm getting older, but if I don't write an idea or todo down in Wunderlist, I will 100% forget about it.
I'm a big advocate for mastering every inch of your code editor. Don't simply learn the basics; harness every inch of productivity you can get out of it.
I try to automate any task that I find myself repeating over and over.
I never touch the Mac dock. I "ctrl+space" everything.