Your question is very open-ended so difficult to answer succinctly.
Are you using an ESL series of books as the basis for your course? If you are following a particular plan, then I would look at the teacher's manuals and see how it progresses through the lessons in teaching English verb forms.
With the progressive tenses, you certainly have to begin with the present tense of the verb "be".
If your students' native language has a progressive tense, you are a long way towards success, since you can map the English form to the same form in their language.