You are using verbs in imperative mode. You can't link two imperatives with "instead of". For example, you can say "Stop!" and you can say "Go!", but you can't say "Stop instead of go!" Instead, you need to reword it so the second command still sounds like a command:
"Stop! Don't go!"
Your third phrase makes sense though. You can say "Stop instead of going!", though it sounds better to say "Instead of going, stop!" The command "Stop!" receives more attention when you place it at the end of the sentence.