Most train companies have a waiting list for training as a driver. (It was around two years with the lot I used to work for). They'll always give precedence to trained drivers transferring from other companies because of the cost of training a new driver (which typically takes around 18 months). Additionally, preference may also be given to existing conductors (because they'll have already completed some elements of the training).
Check out the careers pages of the relevant train companies for your area. Even if there's nothing currently advertised, it might be worth contacting the companies to get on their waiting lists:
errr...you didnt ask how to get qualificiations, or how to get experience...you asked how you could get a job without them...because you just wanted one...
Hi, you will need to look for train driver trainee job vacancies. Once you have found one and applied, you will need to pass the assessments and tests. To find out more about the job, and the recruitment process, you can visit http://www.traindrivertrainee.com for information on how to become a train driver. Good luck! That site has all the links to the different train company careers web pages.