Watching the Apple event brings up a question for me. I know nothing about sign language. They have to make new words for different technical fields as new word

Watching the Apple event brings up a question for me. I know nothing about sign language. They have to make new words for different technical fields as new words and technologies get created. I am curious to know how difficult it is to come up with a new sign, is there enough "entropy" for it? I also wonder what the process is. How does one agree upon the sign for a word and how it's codified and disseminated?