SEARCH TOOL WILL HELP

I think you're talking about the time where the Two Gardens are fighting against each other. If not, better explain yourself better.

What you gotta do is get Squall. Squall will get all frustrated and everyone will scorn him. He makes his big motivating speech and starts to go after Rinoa. Go to the 2ND FLOOR and help the lady find the junior SeeD. You'll find the kid DOWN THE HALL. When you tell him to go back to the Female SeeD, a Galbadian Soldier on those hovers will attack you.

This is where it gets tricky:
First, press X and it'll give you options. You'll get like "Fight" or "Run Away." Choose the "LOOK FOR MORE OPTIONS." Press X again and then you'll get more options. Choose "PRESS EMERGENCY EXIT" Or something like that. Then you'll fight the guy in the air and save Rinoa in the process.

Hope it helped. Next time make the effort to use the Search Forum tool. People are brutal about this.