The solo student pilot reported that, during approach, he felt a "slight sink". He added that the main landing gears touched down and the airplane began to porpoise. The student pilot added power to initiate a go-around, but the airplane veered left. The porpoising continued, so the pilot reduced power to idle and attempted to use brakes to steer. The airplane exited the runway to the left and impacted a taxiway sign.
The airplane sustained substantial damage to the right wing.
The student pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation.