How do you text people from your number and not from your Apple ID email?

I've recently went to an Apple store and the guy reset all my settings. Lately, whenever I text people with iPhones, they tell me that I don't text from my number anymore, but from my Apple ID email. I tried going into Settings and changing some things, and texting some of my friends to see if it's changed but they keep saying I'm still texting from my email. How do I reverse this or text from my regular number?