Although he was born in 1971 in New Westminster, British Columbia and raised in Coquitlam, Carlo began his professional career in Italy at the age of 16, spending four years with Giorgione and Pievigina of Serie C. He then came back to Canada for the 1992 Canadian Soccer League season with Winnipeg Fury, where he scored ten goals in 24 games, helping the Fury to win the Canadian Soccer League championship. It proved to be the start of a stellar career in the beautiful game, most of which was played in England with four different clubs.
Following the demise of the Canadian Soccer League at the end of the 1992 season, Carlo moved to the Vancouver 86ers. He played there in the American Professional Soccer League before venturing overseas once again, to play for Cambridge United. By 1994, Carlo had scored 39 goals in 105 games, before being transferred to Plymouth at the end of the season. In the summer of 1998, Carlo left the balmy south coast and returned to the midlands to play for Northampton Town. But by the summer of 2000 another move was afoot, and it was on to Oldham Athletic in Lancashire, where he would remain for the next few years. Carlo ended his English playing career in 2003 after an astonishing 367 games totalling 111 goals, thus exploding the myth that Canadians can't put the ball in the net.
After all those years, Carlo still found the time to return home and play for his country. In 1989 he was a member of the Francophone Games team that won a Gold Medal in Morocco. The climax of his international career came in 2000 when he was a member of the Canadian National Team that won the CONCACAF Gold Cup in Los Angeles. He scored from a penalty kick in the final game, and won the Golden Boot as the tournament's top scorer. His international career ended with a World Cup qualifying game against Costa Rica in Burnaby in 2004. His club career ended with the Whitecaps in 2005 playing in the United Soccer Leagues.