Share shell script: file permissions question
You can instruct your friends to run it using sh ./test-script.sh. That would not require a chmod +x to be done.

If your friends also use OS X, another alternative is to package it as an app with Automator using the Run Shell Script action and share that with your friends. In this case the user can run it just like any other application on the system.

See Creating Shell Script Actions in the Automator Programming Guide.