some more on setting up for refactoring

install-go.md

@@ -117,6 +117,29 @@ go get -u github.com/alecthomas/gometalinter
 gometalinter --install
 ```
 
+## Refactoring and your tooling
+
+A big emphasis of this book is around the importance of refactoring. So many people practicing TDD forget or neglect this step. 
+
+Your tools can help you do bigger refactoring with confidence. 
+
+You should be familiar enough with your editor to perform the following with a simple key combination:
+
+- **Extract/Inline variable**. Being able to take magic values and give them a name lets you simplify your code quickly
+- **Extract method/function**. It is vital to be able to take a section of code and extract functions/methods
+- **Rename**. You should be able to confidently rename symbols across files.
+- **go fmt**. Go has an opinioned formatter called `go fmt`. Your editor should be running this on every file save.
+- **Run tests**. It goes without saying that you should be able to do any of the above and then quickly re-run your tests to ensure your refactoring hasn't broken anything
+
+In addition, to help you work with your code you should be able to: 
+
+- **View function signature** - You should never be unsure how to call a function in Go. Your IDE should describe a function in terms of its documentation, its parameters and what it returns.
+- **View function definition** - If it's still not clear what a function does, you should be able to jump to the source code and try and figure it out yourself.
+- **Find usages of a symbol** Being able to see the contest of a function being called can help your decision process when refactoring.
+
+
+Mastering your tools will help you concentrate on the code and reduce context switching.
+
 ## Wrapping up
 
 At this point you should have Go installed, an editor available and some basic tooling in place.  Go has a very large ecosystem of third party products.  We have identified a few useful components here, for a more complete list see https://awesome-go.com.