I put the image into the paint program and enlarged it. I also changed the picture a little as I went (avoiding direct plagiarism) - making edges slightly rounder, etc. to make it easier to cut out. You could also have image enlarged at photocopy shop.
Birds silhouettes cut out of various bright papers also look great - if you wanted a picture to put inside a frame. Have also seen bird silhouettes cut out of paper and attached to plates and hung on a wall - nice (though my hubby feels plates are for eating from not for hanging :)