YES!! Turn your printer off at the end of each day and leave it off if you're not using it for extended periods. Resist the urge to use a power bar to turn off the printer. Doing so could prevent the printer from "parking" the print head in the correct position (protective pad or cap inside the printer). This helps prevent ink from drying and clogging inside the print nozzles.
Newer printer models are "Energy Star Compliant" and automatically park the print head after a sustained period of inactivity.