He began his television career in 1992 co-hosting Network Ten's youth music show, Level 23.
In 1996 he co-hosted Sydney Children's Hospital Telethon alongside Julia Morris, and Space Probe 7 with Melissa George for Seven Network.
In that year Testoni won the Most Popular New Talent category at the Logie Awards of 1996 for his work on Home and Away.
He wrote and produced the documentary film, Mr Patterns (2004), which depicts the teaching work of Geoff Bardon, it broadcast on ABC-TV in 2005.
[2] It was screened at the 2004 Melbourne International Film Festival,[3] where Testoni received the Award for Emerging Australian Filmmaker.