Qualifications
Technically, all you really need to become an endoscopy technician is a high school diploma. It never hurts to go above and beyond, though, so consider getting an associate's degree or a few certifications. Neither take as long to earn as a bachelor's, they're nowhere near as expensive, and they'll still boost your chances of landing a job—and a better starting salary (source).
You'll also need to have the stamina to be on your feet all day, a strong stomach, and some great people skills. The prospect of having someone take a look inside your guts with a little camera on a bendy straw can make patients feel pretty #awkward. Bone up on those clear communication skills—you'll need them when you have to explain exactly what you're going to do without making it sound scary.