Sims enjoyed a standout prep career at Mize Attendance Center in Mississippi competing in football as well as track and field.

Sims transferred to West Texas A&M where he was recognized as Lone Star Conference Co-Defensive Lineman of the Year in 2008.

As a senior in 2009 Sims was the Buffs' leading tackler among down linemen, recording 20 total tackles (10 solo, 10 assists).

He also had a team-high 13.5 tackles for losses, as well as 7.0 sacks, five pass breakups, five quarterback hurries, two blocked kicks, three forced fumbles and one safety.

Sims was named Lone Star Conference Defensive Lineman of the Year for a second consecutive season, as well as being a First-team All-LSC South Division selection.