Having gameday style means incorporating lots of pieces in your team colors into your wardrobe. I have always found myself stocking up in seasons where my colors were plentiful in the trends. If you want to stay ahead of the game on what colors are in, and knowing whether your own team colors happen to be popular for that season, just Google the term "Pantone Fall Trends".
It's like the Pre-season Top 10 when determining what team colors are on-trend for the season. Don't feel sartorially challenged if your favorites aren't represented... your own school or team colors are always a classic on gameday. If your colors happen to appear on the Pantone color chart, it means they will be all over the shops and stores and you better get in gear and stock yourself up.