Hi and welcome to the Forums.
Go and look at as many training facilities as you are able too. Meet the staff and the tutors who you are going to be working with on a day to day basis. Talk to the students training there and if possible do so when the tutors are not present as they may not give you accurate feedback if there is anything they are not happy about.
Decide what you are looking to achieve by the end of your training and then choose a suitable provider to deliver that training.
Some specialise in short 1 week intensive courses and others such as my company specialise in longer in depth 6 week courses.
Make sure that the course covers practical / theory / marketing / business start up / products available etc.
We only employ fully qualified tutors to deliver training and we have industry experts deliver the business start up sessions and qualified marketing experts who guide you through that side of things.
I hope this helps