Spin a yarn

Pronunciation	/spɪn ə jɑːn/ (スピン・ア・ヤーン)
Part of Speech	phrase
English Definition	To tell a long, often exaggerated or entertaining story — which may be true, embellished, or entirely made up.
Japanese Translation	長い話をする、（誇張気味の）話を語る
Japanese Explanation	本当の話でも、大げさな話でも、作り話でも、話術そのものを楽しむことを意味する表現。

Origin

Figurative use of 'yarn' (a length of thread/wool) as a metaphor for a long, winding story — the storyteller 'spins' it out.