The September and November BOT meetings are scheduled during weeks of home games.
On those weekends, the President hosts a tailgate in Medlar Field (actually, she does that every game - but specifically including the trustees on those two dates There are always a lot of invited guests, donors, etc). Trustees are invited (along with a guest) to attend the tailgate, and to get passes for the game - to watch from the President's Suite (which is huge - like 100-150 seats, and a big common area)
Big buffets open for hours and hours, open bar, etc - as you might imagine, it is pretty nice
Many of the Trustees have their own suites - or at least blocks of tickets.... so not everyone takes advantage of that invitation (I did for one of them last year - I think it was the Maryland game. I think the other was for the CMU game.... which I didn't go to). I would guess maybe 2/3 or so of the 36 do take advantage of the tickets.
That said, in addition to those games, Trustees can request suite tickets for any game, and in larger quantities - but those are dealt with on a "space available basis" My wife and I did that for one of the cold weather games last year - I think MSU.
Trustees can also ask the Board office to help them procure "regular tickets" (bleacher seats) - but pay the going rate for them (usually there are some held back by the Development Office and what not for any last minute requests from big donors and such things).
Trustees also get an "All Access" pass for once they are in the stadium (at least they did last year - I haven't heard anything about this year) that - I am told - allows them to access other parts of the stadium or to go down on the field for the game. I was told it can be used to attend the post-game PC, visit the locker room after the game, and what not.... but - aside from going down to field level before a White Out game, to see what that looked like from down there (it is quite the view, FWIW) - I've never done any of that, so I can't say for certain if that is true.