auf großem Fuß leben

Etymology
lit. 'to live on a big foot'. Compare, of which it may be a calque; further also 🇨🇬, 🇨🇬, etc. First attested in German in the 17th century. It derives from “foot” in the sense of “basis, foundation” and thus “way, manner”, here referring to expenditures. Compare,.

An incorrect folk etymology derives it from the long, pointed crackow shoes worn by aristocrats in the 14th and 15th centuries, with the longest points worn by the most noble individuals.

Verb

 * 1)  to have an expensive life-style, to live the high life