> Work 6 days per week. Use that saturday to work on things that are harder to do during the week because of interruptions.

In my own case I haven't found it necessary to overwork. In fact, if overworking was the only way to make it I'd probably become an employee. My current schedule is 4 days / week, consisting of 8 hour work days. Three of those days are for billable work, one for other stuff (bookkeeping, sales, blogging, keeping up with HN :P). I plan to write a proper article with more details by the end of this year, when I feel I have enough things to tell.