Self Sponsorship
My College housemate BennyClub speaks with authority on the subject of ATCO training outside NATS. Having just done the APS (alongside Benny) as a first civil controller course at Cwmbran you can expect a steep but generally acceptable learning curve. The only suggestion that I would add to Clubhead's spiele is that you may want to speak to any listening SATCO's on the possibilty of recruitment as an ATC Assistant doing the job as a 2-3 year lead in to becoming an ATCO. You will gain invaluable experience as an assistant and later could potentially be sponsored through a controller's course whilst being paid. There are many different routes to wearing a civil controller's headset. Some are expensive, my Basic and APS course set me back £20K, and others are potentially free, i.e. ATC Assistant first followed by controller training later. Nothing is cast iron nor guaranteed so you pay or not pays your money etc....Good luck.