Changes from Development to Production Environment

Dear Community,
I am new to ErpNext and this forum. FIrst, I would like to thank you for such a beautiful software packed with features. I have question regarding carrying the changes from development ErpNext to production ErpNext. We have two deployments of ErpNext on One deployment runs production server and the other is used to do development, mostly related to custom webpage, custom docTypes, adding some scripts in ErpNext all using the GUI provided. After testing all these, I want to make the same changes to production environment. What is the best way? If there is a utility to mark different versions of the changes or link it with GitHub, it would be great.