How to edit an actionmap

Hi. I’m trying to learn how to use actionmaps. Specifically, I’d like to know how to add a new input. I’ve been using the samplesroject for a while and I can use the player actionmap with the ‘moveforward’ ,ect, definitions like a champ.

But how/where do I edit the file that will allow me to add another input definition. There’s a lot of defaultprofile.xmls and actionmap.xmls all over the place in different folders and the official documentation doesn’t really specify which files exactly to alter.

Also, do I have to rebuild the project or what?

Check these two docs: http://docs.aws.amazon.com/lumberyard/latest/userguide/fg-nodes-creating.html and http://docs.aws.amazon.com/lumberyard/latest/developerguide/controllers-setting-controls.html