You dont need photoshop for that just use MS paints. From your photo cut a portion with your face covering 50% approx. the size of the potion u cut could be any dimension, but to avoid image skew maintain the proportion of height and width. Then paste it to new file. Then you can check the attributes of the photo which will show the pixels for height and width. then use a calculater to find out the % by which they need to be stretched. Go to the option stretch/skew and type appropriate %. Again check the attribute and type in to fix it to 240x320. If you need help, send your photo to my email address. I will fix it and send back to you. Allow me 24 hrs for that in case I checked my email late.