mod readme

README.md

@@ -1,2 +1,24 @@
 # GoSwitch
+
 Easily switch GOPATH working directory
+
+## Install
+
+### Build from source
+
+- Install Go from https://golang.org/
+- Setup GOPATH, tutorial: https://github.com/golang/go/wiki/SettingGOPATH
+- Download GoSwitch source on Release tab.
+- Get dependencies, `go get gopkg.in/alecthomas/kingpin.v2`
+- Build, `go build goswitch.go`
+
+### Add to PATH
+
+Add goswitch executable to PATH variable, so you can access goswitch everywhere on cmd/terminal
+
+#### Windows
+
+- Copy `goswitch.exe` to `C:\Program Files\GoSwitch\goswitch.exe`
+- Open `Control Panel` -> `System and Security` -> `System` -> `Advanced system settings` -> Click button `Environment Variables..`
+- On tab User variables for %user%, edit `PATH` and add `;C:\Program Files\GoSwitch` on end of text
+- Open new CMD, type `goswitch`