When I write a sports story I have a very simple way of gathering all the facts and information to include in my story. I take notes of play-by-play actions for most sports like football and soccer, and at the end of the game I compile stats for the leading players that are of note to include in my stories. For non-sports stories, I sometimes write bullet points of things to include, have multiple research tabs open, and keep track of any links that I may have used for information.
This is a picture of a page of the notes I take during football games. While it is messy, I am able to read it and I use it to keep track of major plays and plater stats.