How do I install Draw Arrow for Gimp 2.8 on Mac?

Hi there. I am relatively new to gimp, especially 2.8 (and mac) and I cannot seem to figure out how to get it to install. I tried to open arrow.scm in Gimp and I have no idea where it went. I looked at my plugins and scripts folders but I can't figure out how to copy or install the plugin. I feel really stupid. Currently, I am deployed in the Philippines and I don't have much time. If someone can give me a step-by-step (dummy proof, or as we say in the Army, private proof) guide, I would greatly appreciate it. Thank you very much in advance.