The rule is the same as that for any other compound adjective: used attributively (that is, before the noun or pronoun they modify), they are hyphenated; used appositively (that is, after the noun) or predicatively (after a copulative verb), they are not hyphenated. He was a well-liked man.

Do you hyphenate well positioned?

Bear in mind that the position of well is merely an indication that a hyphen may be required; its placement in a sentence is not a guarantee. Here are some exceptions that prove the rule: Mike Weir won the golf tournament with a well-timed shot. Mike Weir won the golf tournament with a shot that was well-timed.

How do you use well versed?

They would be persons well versed in the facilities available to help women in difficulties with their pregnancies. At any rate, he was well versed in the literature of the subject. The city is rich in archaeological remains and is well versed in these matters.