Code review. Just do it.
There is one practice that has had more of an impact on my professional programming life than anything else–code review.
The role of code review at Google has been pretty well-documented by now. It is absolutely central to the way it builds and operates engineering systems. There is a small river of posts by programmers about how great code review is. And I’m going to add to that, because I don’t think is is something that can be stressed enough.
No matter how great or experienced a programmer you are, code review will always improve your code.
The sad truth is that you are blind to your own code. Once it compiles and runs and does what you want it to do, you don’t want to go over it agian. “It runs! Ship it!” No. A fresh pair of eyes will tell you exactly what you missed. And you will go, “Doh! Shoulda fixed that.”