Sit in a comfortable chair, have your favorite beverage at hand, place your drawing journal on the table or desk before you and just scribble. Clear your mind while you scribble. Scribbling is a good warm up exercise, like stretching your muscles before a workout. Turn the page, then scribble with a plan. Try this warm up exercise:
Put your pencil on the paper and don't lift till you have made lines all over the paper, trying not to let your line cross over itself. Just play and watch the mark flow from end of your writing instrument. Don't think about chores, just enjoy your time with your journal. One continuous line.
Now draw your garbage picture for the day. Fill that journal, baby, fill those pages.