Assuming you mean a comma- this gets very tricky. Normally, when you have several adjective describing the same noun, you use commas between them. "He lived in a small, quaint, yellow house." But sometimes you have an adverb that describes the adjective, not the noun. "He lived in a fairly small house." "fairly" modifies "small", not "house", so you don't separate it with a comma.
Hyphens are used sometime when there's a compound noun, or a pair of words bound together. "He was a well-trained commando." "It was a half-ruined house" There's no hard and fast rule about this- it's more based on usage. Look the pair of words up as one term on dictionary.com if you're in doubt.