Nicholson is a product of the Long Beach basketball community. He attended Millikan High School and played for Bill O’Dell. The he attended East Central Oklahoma State University as a walk-on.

He has held coaching positions at Valley Christian, Garden Grove Pacifica, St. Anthony, Orange, Mayfair, Verbum Dei and Brea Olinda, and is the defensive coordinator for Los Angeles Rockfish. He's won three Suburban League titles and produced multiple League MVP, All-League, CIF and All City selections.

He's board member of the Southern California Interscholastic Coaches Association and is a father of three to Taylor, Cody and Joseph. He enjoys reading, cooking and golf.