How hard is it to become an air traffic controller?

I'll be 18 in a few months and would like to become an air traffic controller. I know you can become an ATC if you go to school or if you've had 3 years of work experience. I've been working part time for the past 4 years at a job unrelated to ATC. I know positions open up when people start to retire. Will there be many people retireing within the next year or 2? How hard is it to get a ATC job without getting the degree? I'd rather not spend 2 years in school if I can just get the job, but I don't want to spend 2 years waiting for a position when I could've gone to school.