Writing requires fortitude. You can't always pick and choose the time or day you will be able to write.  Try to set aside some time each day. The same time would be best but life doesn't work that way. Even if you only write a few sentences, you've accomplished your goal for the day. Take time to look out the window too. It just might give you an idea to incorporate into your writing. Gotta go. Laundry is calling.