Sau hails from the village of Nabukeru Yasawa[4] and attended Yasawa High School before he moved to Lautoka to finish his Year 13 at Ba Provincial Freebird Institute where he was introduced to play Rugby league, He joined Saru Dragons and was given a contract to play in the Cook Islands.
Later he met Lagilagi Golea (FNRL development officer),[5] who urged him to join a 7s team and contacted Red Rock Rugby Club coach, the late Lote Rasiga. Sau joined the team in Qauai and even toured with the team to Australia.
In 2014 he was recruited as a special constable at Totogo Police Station in Suva and joined the Fiji Police Rugby Team.