If you need to get to the university using public transportation, the cheapest ticket (even though it might at first not seem like it) is the “Semesterticket”, costing approximately 195€ per semester (not per month!).
You can buy it at every railway station, every U-Bahn Station and very many tram stations as well as on buses. Therefore you will need your 11-digit MUAS student ID number, which you can simply find on your student ID. Make sure you’re selecting the correct semester (winter or summer) and don’t forget to always have an official ID to confirm that it’s you using the ticket if there is a strict ticket inspector.