Set the Working Folder of `.app` Created by Apple Script
One way to handle this is to set a variable, e.g. myPath, and build out from there.

set myPath to POSIX path of (path to me as text)


The myPath variable will be returned in the form of:

/path/to/AppName.app/


You can then concatenate  myPath and addition path segments and filename as needed.

Note that when using this in a do shell script command, use quoted form of to allow for spaces in the path filename.



Have a look at the AppleScript Language Guide and more specifically: path to (application)


  path to (application)
  
  Returns the location of the specified application.
  
  ...
  
  &nbsp;&nbsp;me 
  
  &nbsp;&nbsp;&nbsp;&nbsp;The script itself. For script
  applications, this is the same as current application, but for script
  documents, it is the location of the document.