I do all my work in Photoshop so these steps pertain to that program. As far as using other graphics programs, this should at least give you an idea of what to do. Did plan on having more images to show the steps, but I am limited to 4 in a post.
The dimensions for the PSP wallpapers have to be 480x272. I am not sure what DPI it will support, but I use 72dpi.
I have a template that I have and use for making my PSP wallpapers. You can get it from
It has two layers to it. The bottom layer is just a 480x272 white rectangle and the top layer is the overlay I use in black.
You can also create a new image at 480x272 at 72dpi.
The next step would be to open the image you want to use as a wallpaper. I suggest that you only use images that are at least 480x272 or bigger at 72dpi. You can check it after you open the file by selecting Image and them Image Size.
The next thing you want to do is crop the image before you resize it. This can be the tricky spot. You need to decide what you want from the image to be used in your wallpaper. Either figure out what you want from top to bottom or left to right. I find it hard to pick both for the most part because I can not crop something that would be 480x272 just by sight. If you want top to bottom, make sure you crop extra on the sides. If you want left to right, make sure you crop extra on the top and bottom. Not sure how much sense that makes. The bottom line is to crop it close to what you want, but leave extra space because you are not going to be able to crop it perfectly.
Now you resize the image. Remember if you need to change the dpi from something like 300 to 72, input the 72dpi before you input your dimension changes because it automatically alters the height and width when you change the DPI. Either enter 480 for the width or 272 for the height, not both. If you try to force it to be 480x272, it will distort the image. Also if you decided to set the height at 272, make sure the width is greater than 480. Or if you set the width to 480, make sure the height is greater than 272. If it doesn’t work one way, try the other.
Select all to copy the cropped/resized image. Select the blank image you created earlier or the template and paste your image into it as a new layer. The reason I do this is because even though you tell it to be 480x272 at 72dpi, it may end up being off a little.
If you just created a blank image in the beginning, you can just save it now and put it on your PSP. I use JPG format to save mine, but I am sure it supports other file formats.
If you used the template you have some option. You can move the image so it is the top layer and just save it and it will not have the overlay.
If you are going to use the overlay, which I suggest for brighter images, make sure it is the top layer over the image. Then adjust to opacity of the layer to something you like. I normally use around 25-35% opacity for mine. After you have that set, just save the image and you are done.