100% this. Write test for everything, don't do manual testing. If the test is green my code is good. Don't spend time manually testing your code. Touch typing

100% this. Write test for everything, don't do manual testing. If the test is green my code is good. Don't spend time manually testing your code. Touch typing was a huge improvement. I'm not a fast touch typer so it wasn't really improved my typing speed. It's more of that I outsourced my typing from my brain to my hand, so while I type I can stay focused on the problem.