The way I see it you have 3 options and becoming an aeonautical radio officer isn't one so if you want to count that its 4, but thats not ATC.
You can go by self-sponsorship. Go to ASTAC in England get the training and come back here, do the test and get your license and wait for a vacancy to come up in a regional or something.
Get sponsored. If an airport wants atco's they may pay for your training. They'll send you somewhere like ASTAC in England and you come back, get your license and work for them. Same as previous only your being funded and you have a job to come back to.
Thirdly you can go via the IAA. This is the most mainstream and common but the others do pop up often enough, generally there is in and around 3 to 4 atco positions that become available on an average year.