26.
Form the nose. Check the size and shape with the photo. Stick it on. Use a bone tool or a ball tool to make indentations for the eyes. Always check the positioning of each face feature with the photo - it's important when making movie/cartoon characters - sometimes a few mm make a huge difference ;) Oh and I find it useful to print out an additional photo which shows the face from the front - it's easier to position the smile, nose and eyes that way :)