I agree with the ideas from others that you might want to build yourself up a bit. But 6 miles is not a terribly long way to ride as long as you give yourself the time to do it. And then you've got the day to recover before you head back on another 6 mile ride.

Especially good is the idea to ride your planned route on your day off.

As for progression after you get started, I suggest letting your body tell you when to increase the number of days in the week that you ride.