McFadden has been exceptional for Scotland, but is yet to catch fire in a Birmingham shirt.
He told the Sunday Mirror: "I'm sure the fans will get to see the best of me now. I've started the season better, especially the last couple of games.
"I had a little injury after a few games, but in the last couple of matches they have seen glimpses of what I can do.
"It's up to me to reach the levels of consistency and performance and show the fans what I can do."