Experimental. It will sometimes render the suit not noticeably large enough. "in an oversized gray suit" is the prompt used for the actual photos of the suit, so use that if you want the suit he wore, but any color works while sticking with the style of the suit.

Main trigger prompts are:

TalkingHeadsSuit, in an oversized (color) suit,

Other prompts that seem to help:

Positive: large suit, big suit,

Negative: small suit, blurry, film grain,