Activities for 5 year old pre-game in the stadium

I'm taking my son to his first game tomorrow and we're going to arrive at the stadium early so that he can soak up the experience. Just wondering if there are any things that kids can do or tips on meeting Gunnersaurus? We're sat just behind the Borussia Dortmund bench so should be relatively close to the pitch but I want him to have the best possible experience as his first game. I'm assuming the penalties at half-time stuff is all pre-selected.

Even though I've had a ST for 20 years this has never been on my radar before!