Digital images, whether they were scanned into a computer from original photographs, computer generated or taken on a digital camera, sometimes need to be re-sized if they are to be printed out. Although it is possible for most modern printing software to shrink an image down to fit on a set page size, such as standard 4x6 photographic paper, this is not always appropriate. Knowing how to resize pictures to 4x6 yourself avoids the necessity of setting individual page sizes on printers for each image and means anyone can print the picture without fuss.
Open your image editing software, such as Photoshop, Paint Shop Pro or The Gimp. Click the "File" menu and select "Open." Browse to the folder where the image to be edited is stored. Select the image. Click "Okay." The image will now load into your editing software.
Click the "Edit" menu and select "Resize image." A dialog box will appear asking you to set the size of the image. Set the horizontal and vertical units to "inches" for both horizontal and vertical sizes. If the image is in landscape format, set the width to 6 and the height to 4. Alternatively, if the image is in portrait alignment, set the height to 6 and the width to 4.
Click "Okay." The image will now be shrunk or enlarged to the correct picture size, depending on how big it originally was. Click the "File" menu and select either "Save" or "Save As," depending on whether you want to overwrite the original file or not. If you do, click "Save," otherwise click "Save As" and enter a new file name.