Simply find an image you like that is either on your computer or the internet, right click on it and click on the option that say make this picture my background or something along those lines.
yea but it doesn't have an option to put it as my wallpaper
pick a picture then right click on it click save to and choose pictures then wait for it to download it onto pictures then exit out of the page then right click on your current picture and choose personalize go to desktop background and choose browse then pick your username and then pick my pictures and select OK and the picture will be there right click on it and choose select and then it will be your wallpaper this is for Acer computers only Thx