Preparing artwork files
You can use any image editing software or this task. Make images of the sleeves in 1440x1440 pixels in JPG, PNG and BMP format.
If you don't have the knowledge to do this we suggest you to ask the designer of the sleeves to make the JPG/PNG images for you. They most certainly have this knowledge.
Look in the MENU under IMAGE and select IMAGE SIZE.
|Free Image Editors|
If you don't have Photoshop you can try any of the following freeware editors.