Speeding drivers and narrow turning spaces were among complaints students had in interviews with The Hattiesburg American about the garage that opened in 2011.
Officials went back to the drawing board this past December after a wave of complaints by the university police department and the Student Government Association.
An SGA resolution to fix the parking garage's traffic problems got the ball rolling on the changes.
"It was a mess," said junior Amber Long, a medical technology major. "I think it's gotten a lot better."
Speed limit signs and signs mandating headlight-use are among the improvements. There are also new wrong-way and no-left turn signs, indicating the change from two-way to one-way traffic.
Southern Miss Police Chief Bob Hopkins said complaints have gone down since December.
"We're hoping after one year we'll have a pretty good indication that the changes we made have been effective," he said. "So far, it's showing that they were."