Anything you think is useful for other people. What most people find interesting is how you bought the ticket, how you got to the stadium, the atmosphere in the stadium, food and drinks, comfort, sightlines, things to bring or leave at home, etc. It is not necessary to give a match report, but do mention which match you went to and the date of the match. With regards to stadium tours you could include whether you made reservations, the parts of the stadium visited, the pace of the tour, the guide, whether they had an interesting story to tell, accessibility, etc.
With regards to stadium tours you could include whether you made reservations, the parts of the stadium visited, the pace of the tour, the guide, whether they had an interesting story to tell, accessibility, etc.