I plan on making a wood altar to sell. I want to engrave something on it like “Azazel Protect Me”. But I dont want him to say, “Who the fuck are you? You have never evoked me you little puke. Now I will make your life hell.” Any thoughts?
While I can’t see someone as well-mannered as Azazel calling you a “little puke,” it is indeed rude to carve the name of a spirit you’ve never worked with into an altar, and try to profit from that.
Imagine later in life you’re a famous successful person, a leader in your field, and someone starts trading on your name? It’s very insulting and presumptuous.
Best to find one of the major demons (Azazel, or another) and work with them on this project, ask them for their help with your business in exchange for you making and selling these objects that will assist other magicians and spread their fame - that’s the kind of deal they would probably be interested in, and you’d get more help that way. 
At the very least, evoke him, or ask him to walk with you on this, and get some divination done to show whether he favours that idea.