Collegiate is quite close to the Hallamshire Hospital which adds to the challenge, you can park in the suburbs (eg Fulwood, Crosspool or Crookes) and get a bus down but there is still some walking to do. FWIW I used to get to train station and ebike (there is secure parking at station)
If you are early and dont mind a walk there is parking on lots of back streets (that aren't residents only) a little way out, for example you can park near Endcliffe Park and walk in. If you arrive a little later in the day (after 9:30?) you can park for free on the road out from Hunters Bar but the bus lanes start up again at 4pm