I think I would recommend the teacher to get to know the class and the level of the students before starting...

I think I would recommend the teacher to get to know the class and the level of the students before starting creating materials. Start out by using something known and then see what is lacking in the printed/online material that is already there. Creating materials is so funny but takes a lot of time, so it really has to be worth it. - Then I would probably teach my colleague to use a vocabprofiler as it is one of the most helpful tools at all for analysing an authentic text