Open Paint or your other graphic editing program. Select "File" from the top menu then "New." Create a file that is either 912 x 912 pixels big or 4.94 x 4.94 inches big. This is a standard CD and album cover size and will fit your mixed tape correctly.
Start by placing choosing a background color. Select the paint bucket tool from the tools palette on the left of the screen, then select a color for it. Place the paint bucket anywhere on the design and click to add the color.
Add text to the image. Select the Type tool from your Tool Palette. This will look like an uppercase "T." Click on the part of the image you want to place your text, then type it with your keyboard. The text should describe something about the mixed tape, such as "Dance Mix." Choose your font and size from the drop-down menu in your Properties bar at the top of the screen. The text should take up about a quarter to a third of the entire space.
Incorporate elements from the songs on your mixed tape in to the design of the cover. This can be direct references to the songs, such as pictures of bands, or pictures that represent the feel. For instance, if your mix is very upbeat you can add some fire to the image to let the person you are giving it to know that it will be hot.
Click "File" then "Export" when you are finished with your design. Choose JPG from the "Filetype" drop-down menu and save it. If you are sending your mixed tape digitally, simply include this file when you send it. If you burning your mixed tape on a CD, then print out your image and cut it out, then place it in your CD jewel case sleeve.