A method for operating a messaging system for sending modifiable videos including a self-image of a user is provided. The method includes providing a face outline to assist with taking the self-image. Instructions relating to a light level, a facial expression, a face position, and a face size may be provided to the user. A smile measurement is displayed to enable the user to adjust the current smile level to a target smile level. A stock video may be created using an actor wearing a mask and facing a video camera. The mask is a marker for insertion of the self-image. The stock video is uploaded to a database of stock videos and, after selection by a user, is combined with a self-image to form a personalized video.