You need to go to "Settings" --> "Developer Options" --> "Select debug app" on you Actual Device.

After clicking on "Select debug app", there will be a list of your installed apps, Select the app you want to run.

That is it you will not see the "Waiting For Debugger" message any more.

you need to enable Debug Mode and then resign the app.

​

this link explains how:

https://www.evilsocket.net/2017/04/27/Android-Applications-Reversing-101/#Debugging

Go to Run menu ====> click on Edit Configurations ====> Micellaneous and finaly uncheck the option Skip installation if APK has not changed