Summer vacation

I'm plannning to go to Osaka with my club member. I have never been to Osaka, so I'm looking foreward to going there. That plan is three day trip. First day, and second day,we will go to Universal Studios Japan. And third day, we will sight seeing in Osaka city. But it cost much money. So I have to earn more than ever! Have you been to Osaka? What is the famous souvenir? When we sightsee in Osaka city, where should we go to???