it is pretty easy to get there. no worries!
the ticket question is kinda more complicated - cause of the very weird ticket system here in munich.
it depends on where you live, where you wanna go and how many days you're planning to use subway/bus/tram/s-bahn. subway station "studentenstadt" (where the tournament takes place, pretty close to the northern part of englischer garten by the way...) still is in "innenraum (inner district, the white area on the subway-map) (1.-4. ring)", the central part of the city. if you also live in this area and are not planning to leave it, i would recommend you a 3-day-ticket inner district from friday to sunday and another one from monday to wednesday. the price (around 12 euro per ticket) is ok and you can use everything as often and whenever you want to (in the inner district).