First, we recommend you inform yourself about vocational training. When you decide what type of training you want to do, you need to look for a company and/or a vocational school. To find available places you can use for example the homepage of the Bundesagentur für Arbeit (Enter the keyword “Ausbildung” to do your research). You can also ask directly at a company if they accept trainees.
After finding a training place you are interested in, apply for it directly (at the company or the vocational school). Keep in mind that some companies or schools look for trainees long before the training starts, in some cases even more than a year before. So start searching and preparing early in advance. The requested application documents, application deadlines and ways of sending in the application will be explained on the homepage or in the advertisement of the company or school. In general, you have to send in a CV, letter of motivation, your school diploma and sometimes, additional documents. As a refugee, you may also have to prove your language level and your legal status.
If a company found your application interesting, they will probably invite you to an interview to get to know you better. This is also a good chance for you to find out more about the company and the people working there. For general tips about preparing an interview, read more here.