Gardner spent all his career with Villa before making a £3million move to St Andrew's during the January transfer window after becoming frustrated with his lack of first team opportunities.
He would like to make an impact on his return to Villa Park as City look to avenge a 1-0 reversal earlier in the campaign against their Second City rivals.
But Gardner has no bad feelings towards Villa or their manager Martin O'Neill and any joy at finding the net will be muted.
The former England Under-21 player said: "It is going to be a massive game, especially with myself being a Blues fan, and going to Villa Park and playing in the Blues strip. I just can't wait.
"What reception I get will be up to the fans. I've moved on. It's nothing to do with the club. The club were brilliant to me and the manager. I haven't got a bad thing to say about the club."
Gardner is hoping for a sympathetic reception from the home supporters, adding: "I don't think I deserve stick but if I get a bad reception, I'm not going to take it out on anyone.
"I'm just going to get on with it, just get on with the job. I'd love to score the winner on Sunday but I wouldn't celebrate over the top.
"Of course, it could be the last goal you score in your career so you've got to celebrate but I wouldn't rub their noses in it. I'm not that sort of person.
"If you score, you deserve the right to celebrate whether it's at Villa, Manchester United, anywhere."
Gardner believes there is more to Birmingham than a team of battlers.
He said: "People think Blues are just a team who fight and scrap every time but we are more than that and we've had good results against the top teams.
"We try and get the ball down and play, let the ball do the work and it shows on the pitch and it shows in the results we've got this season already."