What advice would I offer my younger self?
Manny Medina's company, Outreach, is valued at $1.1bn (£840m) - but he took a long, uncertain route to success.
What advice would he offer his younger self? If someone offers to fund your young company, don't let them off the hook. Send them your bank details the next day.
'Just ask, very bluntly, "when will you have it?",' he says. Otherwise you'll be chasing that money for a very long time.
Video journalist: Ian Rose. Studio editor: Rob Miller.