First Sergeant Cepeda enlisted in the Marine Corps and reported to Marine Corps Recruit Depot, San Diego, California in 2004 for recruit training. Upon completion of Administrative Clerks Course, he received the MOS of 0151 and reported to Headquarters Battalion, 3d Marine Division, Okinawa, Japan.
In 2008 First Sergeant Cepeda reported to Marine Air Control Group-38, 3d Marine Aircraft Wing, where he served as the Legal Chief and Administrative Noncommissioned Officer. In September of 2010, he deployed in support of Operation ENDURING FREEDOM. In 2012, First Sergeant Cepeda reported to Headquarters and Headquarters Squadron where he served as the Separations Noncommissioned Officer In Charge (NCOIC), Deployments NCOIC, Corporals Course Instructor/Chief Instructor and Legal Chief.
In January of 2015, First Sergeant Cepeda reported to Combat Assault Battalion, 3d Marine Division, Okinawa, Japan, where is served as the Battalion Administrative and Legal Chief.
In January of 2018, he reported to Drill Instructor School, Marine Corps Recruit Depot, San Diego, California and was promoted to the rank of Gunnery Sergeant. First Sergeant Cepeda was assigned to 3d Recruit Training Battalion where he served as a Drill Instructor and Senior Drill Instructor with Kilo and India Company. He then served as a Chief Drill Instructor for Lima Company. First Sergeant Cepeda then served as the Uniformed Readiness Coordinator, Substance Abuse Control Officer, and Headquarters Company First Sergeant for 3d Battalion. He then went on to serve as the Mike Company First Sergeant until May of 2021.
In May of 2021, First Sergeant Cepeda reported to III MEF Support Battalion, III Marine Information Group, III Marine Expeditionary Force where he served as the Administrative Chief. In February of 2022 First Sergeant Cepeda was promoted to his current rank and received orders to Combat Logistics Battalion 4, Combat Logistics Regiment 3, 3d Marine Logistics Group where he served as Company First Sergeant for Headquarters and Service Company and Motor Transportation Company. In May of 2024 he reported to Deployment Processing Command, Reserve Support Unit-East where he currently serves as the Command Senior Enlisted Leader.
First Sergeant Cepeda's personal awards include the Navy and Marine Corps Commendation Medal (gold star in lieu of 3rd award) and Navy and Marine Corps Achievement Medal (gold star in lieu of 3rd award).