Learn the basic steps of laying tile through self-study and through the resources that you have available to you in your community or online. For example, tile a small room in your own home to get the feel for the process. A retail store that sells tile such as Home Depot often has instructional seminars that can help you learn how to do tile competently. There are also a number of good books on the subject.
Take a course in tile work. There are short courses in tile work that you can take through community colleges and learning centers. This is a good way to get a more formal instruction in tile work from experienced floor workers before you move on to the next step. Additionally, if you have even a little formal instruction, it may help you to get a job with an experienced tile installation worker or company.
Apply for jobs with a company that installs tile professionally. The best way to learn any trade or craft is through hands-on experience under the supervision of an expert in the field. That is why most of the trades are learned through an apprenticeship style of eduction. If you want to become truly proficient at tile work, you need an experienced worker who can correct your mistakes and who can instruct you on the techniques, tips and tricks that the professionals use to make sure that they achieve excellent results on every job that they work on.