In 1919, at age 26, Bachman began his head coaching career at Northwestern University in Evanston, Illinois. Bachman brought a number of former players returning from World War I military service to Northwestern, but his team posted a disappointing 2–5 record. He moved on to Kansas State College in Manhattan, Kansas following this season, and the losing record proved to be an aberration; from 1920 to 1927, Bachman posted a record of 33–23–9 at Kansas State. In 1924, Bachman's K-State team beat the University of Kansas for the first time in eighteen years. Bachman coached Kansas State's first All-American, and under his leadership the school also permanently returned to its former nickname of Wildcats and began using a live bobcat as a mascot.
Bachman accepted the head coaching position at the University of Florida in Gainesville, Florida in 1928, where he posted an 8–1 record his first season, the best in the Florida Gators' history up to that time. The 1928 Gators' sole loss came in their final game of the season, a disappointing 12–13 upset by Robert Neyland's 8–0–1 Tennessee Volunteers in Knoxville. While at Florida, Bachman coached the Gators' first first-team All-American, Hall of Fame endDale Van Sickel, in 1928 and 1929. He also led the 1929 Gators in their first major intersectional match-up, a "neutral site" game in Miami against John McEwan's 7–2 Oregon Ducks football team, with the Gators coming away with the 20–6 victory. Bachman's first two seasons with the Gators were his most successful, but he continued to lead the Gators Eleven for five seasons, posting an overall record of 27–18–3. Dashwood Hicks, a lineman for the Gators in 1928, said "I've never seen a man eat and sleep football like Bachman. He couldn't sit down and talk without drawing plays or something."
Bachman left Florida to become the head football coach of Michigan State College in East Lansing, Michigan, coaching from 1933 to 1942 and from 1944 to 1946. Similar to the situation he inherited at Kansas State, Michigan State had not beaten the University of Michigan for eighteen years (1916–1933), but under Bachman, Michigan State defeated Michigan four consecutive seasons (1934–1937). Bachman's overall record at Michigan State was 70–34–10. His Spartan teams were also notable because he outfitted them in gold and black uniforms instead of the official school colors of green and white.