In her book "Organizing from the Inside-Out" Julie Morgenstern recommends creating a "time map" of your week to get an idea of how much time you have and where you could schedule certain types of activities. The map looks like a page from a weekly appointment calendar. Times are blocked off for when you're *regularly* at work, when you're *regularly* asleep, exercising, at church, etc. The map contains things that are almost guaranteed to be in your hard landscape week-to-week.
It's a useful exercise to see where you might fit things into your time or how many hours of discretionary time you may have available. As you create your time map keep in mind your typical energy levels at given points of a day. If your mental creative energy is highest first in the morning, "schedule" blocks to take advantage of it.
The thing to note is that it's only a guide and you won't necessarily follow it to the letter. For example, if you have time blocked off to take care of laundry on a beautiful Wednesday evening but you can do it Thursday when it's raining, follow your instincts and go enjoy the weather--work or play. You have the freedom to "move the blocks".
Another thing; don't try to fill in every ounce of your time. Leave some discretionary time open to be spontaneous and follow your gut. This exercise really helps you to make sure the "big rocks" are built into your life.
Good luck.