Things You'll Need
Instructions
Turn on your home computer and open the photo editing program you use to edit your pictures. If you do not have a photo editing program, there are many free and for-purchase photo programs you can download off the Internet.
Click "File" or "Get Photo" from the navigation bar of the program and follow the prompts to open the picture you want to enlarge.
Click the icon for the "Crop" tool. This tool will allow you to select the part of the picture you want to print. Set the size of the picture. Depending on the program you are using, this is done using a drop-down menu or by inputting the size into fields in the program. Set the DPI (dots per inch) to a high-quality resolution, such as 300. DPI refers to the level of detail of a print.
Move your computer mouse to position the crop tool at the bottom left corner of where you plan to crop your picture. Draw the tool across the picture and stop at the top right corner of your picture.
Save the photo as a new image. Your picture has now been enlarged to the size you want at 300 DPI for printing.