In this tutorial, we learn how to change image size in Photoshop CS3. First, go to your pictures folder and then open up your picture. From here, reduce the image to 50% of what it is by opening up Photoshop. Load the picture to this, then go to the edit menu of the image and zoom in and out of it to see the image larger or smaller than what you want it. You can also crop it if you want to remove something from the image. When you're finished changing the size, save this to your computer and you're done!