Carson Yeung outlined how in the 1990s he built a chain of upmarket salons and styled hair for celebrities, earning a total of $20 million Hong Kong dollars ($2.6 million) during his hairdressing career.
He dabbled in real estate and bought a Chinese hotel before focusing on stock trading. He told court that by 2000, he was worth 80-100 million Hong Kong dollars ($10-$13 million).
Yeung is charged with five counts of money laundering involving more than HK$720 million deposited in five bank accounts from January 2001 to December 2007. Prosecutors have said the money was "criminal proceeds."
The charges are unrelated to the football team, which Yeung bought in 2009 for 81.5 million pounds (then $130 million) following a protracted takeover battle.
Prosecutors have alleged that vast sums of money flowed through Yeung's accounts even though records show he earned a meagre income during that period.
In May, prosecutors told the court that the money involved was hundreds of times more than the combined income of HK$2.2 million ($278,000) reported for 1999-2006 by Yeung and his father, who ran a vegetable stall and had some of the bank accounts in his name.
Defence lawyer Graham Harris questioned Yeung about his various ventures, part of an effort to portray him as a legitimately successful businessman.
Yeung, 53, told court he apprenticed at salons in Hong Kong, Paris and London, earning about HK$10,000 ($1,230) a month. He set up his own salon in 1989 and added four more throughout the early 1990s, becoming a "very famous" hairdresser whose services were sought after by Hong Kong movie stars.
He and his father bought a hotel in Dongguan, mainland China, which earned them a small income. They later sold it for a small profit. Yeung earned HK$7-$8 million selling property in Thailand and Malaysia to Hong Kong residents eager to leave the then-British colony ahead of its pending handover to China in 1997.
He also earned HK$15 million selling upscale villas in a Hong Kong housing development.
Yeung said he then focused on stock trading, weathering a market crash in 1998 that sent his portfolio down 70 per cent. He used cash and also borrowed money to invest in stocks, with one brokerage giving him a credit limit of HK$80 million.
Prosecutor John Reading has previously told the court that his aim is to establish the source of the money.
Birmingham won the 2011 League Cup, ending 48 years without a major trophy, but despite the victory was relegated from the Premier League the same year.
Before his takeover of Birmingham, Yeung's only experience with professional football consisted of a stint as chairman of Hong Kong Rangers Football Club from 2005-06.