I assume you're looking for a photograph of something real or even a piece of artwork from which you can do some kind of descriptive writing assignment. I'll give you several ideas, but first there are several helpful things to consider so you can find your own photo or piece of artwork to describe.
First, choose something that is somehow familiar. In other words, something which quickly conjures up a familiar or stereotypical image in your readers' minds. For example, if you say it's a picture of a pair of hands which might belong to an elderly woman like a grandmother, the image is automatically set. From there you can be more specific--ring or no ring, shape of the fingernails, lines and wrinkles, or whatever.
Second, if you do choose something unfamiliar, describe it in terms of something your readers would know. For example, if it's a building most people haven't seen, explain that it's in the shape of the Eiffel Tower or the Washington Monument, or whatever other recognizable element we can readily picture.
Third, be as specific as you can when you draw the literal picture with words. Utilize the senses (how rough, how smooth, how fragile are those grandmotherly hands, and how tall or what shape and what texture the building). Rather than stringing together a series of adjectives ("a large gray animal with lots of wrinkles" is not as effective as saying "an old, wrinkled elephant standing majestically, trunk raised in a trumpeting call").
Finally, though this probably should have been first, choose something that moves you in some way. If it does, your description is likely to be much more effective.
Two works of art which you might consider are Grant Woods's American Gothic (better known as the "Corn Flakes" picture) and Norman Rockwell's Freedom From Want (also known as his Thanksgiving painting). Both of these are easily found on line. Gothic is a farm couple (a father and daughter, actually) who has lived a difficult life and it shows on their faces. Lots of good descriptive possibilities here. Freedom is exactly how the most pure, old-fashioned Thanksgiving at Grandma and Grandpa's house must have been.
Whether you choose these kinds of things or something from your own photo album, make sure it's something real and which inspires you in some way. Best of luck!