As an adjective:
* "The company's visionary CEO led them through a period of incredible growth." (Describes the CEO)
* "She had a visionary plan to create a sustainable city." (Describes the plan)
* "Their artistic vision was both visionary and groundbreaking." (Describes the vision)
As a noun:
* "Steve Jobs was a visionary in the field of technology." (Identifies someone with a visionary quality)
* "The artist's work was inspired by the visionary writings of William Blake." (Identifies the source of the inspiration)
* "The architect's visionaries helped transform the cityscape." (Identifies the people responsible for the vision)
As an adverb:
* "The entrepreneur thought visionary about the future of online retail." (Describes the way someone thinks)
The best way to use "visionary" depends on the specific context and what you are trying to convey.