During a 14-year professional career, he appeared in nearly 400 Bundesliga games, mainly representing Schalke 04 (11 years) and later also briefly managing the latter.

Büskens began his career with his hometown team Alemannia Düsseldorf before moving to city giants Fortuna.

After five years, he moved to VfL Benrath, returning in 1987 to Fortuna, this time as member of the professional squad, and rarely missed one top-division game during his three-year spell, although ended in relegation.

In the European conquest of 1997, he played in 10 matches (eight complete), including both legs of the final against Inter Milan.

He continued to play for the team until 2003, splitting between the first and second squads in his last year, also being assistant manager of the latter.

[1] On 13 April 2008, he was appointed caretaker manager of Schalke's first team, alongside another former club player, Youri Mulder, succeeding Mirko Slomka after a 1–5 away loss to Werder Bremen, as the team was battling for a UEFA Champions League position (eventually reaching third).

[2] Büskens remained in charge until the end of the season, being replaced by Fred Rutten in July 2008.

[4] However, in March 2009, the latter was fired, which led to the pair again taking over the side until the end of the season (now accompanied by another former Schalke player, Oliver Reck), being then replaced by Felix Magath,[5] and released by the club on 23 June 2009.

[26] On 7 March 2022, after the dismissal of Dimitrios Grammozis, he took over the team as head coach on an interim basis until the end of the 2021–22 season.