Managing a fast-growing tech start-up is not a job that everyone is cut out for. Managing two of today's hottest start-ups simultaneously? That's a feat that could overwhelm even some of the corporate world's biggest egos. Somehow, Jack Dorsey, the co-founder of microblogging service Twitter and mobile payment company Square, is managing to pull it off, putting in 8 hour days at each of the two companies every day, without collapsing into a pile of jello. How does he do it? Dorsey, who serves as Chairman of Twitter and CEO at Square, shed some light on his double-duty worklife during a talk at the Techonomy conference in Tucson, Arizona recently. The key, Dorsey explained, is to "theme" his workdays, with each day of the week dedicated to specific matters. Below is the schedule of Dorsey's grueling workweek, as explained at the conference: Monday: Focus on Management and running the company - Directional meeting at Square, Op Com meeting at Twitter. Dorsey also has his management one-on-ones on Monday. Tuesday: Focus on product Wednesday: Focus on marketing, communications, growth Thursday: Focus on developers and partnerships Friday: Focus on company and culture; recruiting. "There's interruptions all the time. But I can quickly deal with an interruption and then know that it's Tuesday, I have product meetings and I need to focus on product stuff," Dorsey explained. "It also sets a good cadence for the rest of the company, so that we're always delivering, we're always showing where we were last week and where we're going to be the following week. So it's been good, but we're always evolving," said Dorsey. What about the weekends? Well, Dorsey has a plan there too. On Saturday, said Dorsey, "I take off, I hike." And on Sunday, Dorsey spends time on "reflection and feedback," as well as focusing on strategy and getting ready for the rest of the week. o there you have it, the Dorsey blueprint for running two companies, for anyone with the drive...or the masochism.