I have set a target of 500 words five days a week. I find that while driving around on my own (can't do this with other people in the vehicle) I can come up with enough story line to fill out to 500 words easily. I only have to keep a few days ahead with the plot this way- while working to the story plan, of course.
Break anything down into small bit and it becomes do-able.
500 words, five times a week is nothing- but adds up to 100 k a year!