Even when your store is closed, it can still be working for you! Consider having an LED sign in your window to detail upcoming store events and sales. Make sure the date and hours of the sale or event are clearly readable on your sign. LED is not a fire hazard and doesn't cost a lot to operate. This suggestion is from a trade magazine for gift stores, but equally applies to needlework stores.
Or, you could post a sign "If we are closed, please just shove your money under the door." Please make certain to have your store hours posted in a prominent location. Nothing is more frustrating to a potential customer than to visit your shop when you are closed and not have hours posted (personal experience). We all want to keep those customers happy and Keep on Stitchin'! Beth