 Sills was a product of Millwall's youth system and was a regular in the club's youth team up until he left in 1997.He then joined part-time outfit Camberley Town, spending a year and a half at the club, before moving to Basingstoke Town towards the end of the 1998–99 season.Sills spent three seasons with Basingstoke, playing over 100 games for the club.