Update README.md

Author: LubyRuffy

README.md

@@ -16,6 +16,17 @@ The official library doesn't has unittests,  之前官方的库功能不全，
 
 ## Usage
 
+### Build and run
+
+```
+~ go install github.com/LubyRuffy/gofofa/cmd/fofa@latest
+~ $GOPATH/bin/fofa
+~ $GOPATH/bin/fofa search port=80
+WARN[0000] auth failed
+2022/08/07 14:38:29 auth failed: '[-700] Account Invalid', make sure key is valid
+~ FOFA_CLIENT_URL='https://fofa.info/[email protected]&key=xxx' $GOPATH/bin/fofa search port=80
+```
+
 ### Search
 
 -   search query, only query needed:
@@ -213,4 +224,4 @@ every 500ms generate one line, never stop
 
 ```shell
 ./fofa stats -f domain -s 100 'cert.is_valid=true && (cert="google")'
-```
+```