Nobody responded because this is a duplicate of Need help with custom emotes
As was mentioned in that thread, you can reverse-engineer FrankerFaceZ to find out everything you need to know about injecting emotes into App.EmoticonController. Alternatively you can investigate BetterTTV’s approach.
Perhaps if you have specific questions on what a piece of code is doing, you can ask about that. A general “how do I do X?” is rarely going to be answered properly.