This pattern is based on my own sleeve for my Kobo Clara 2E (12 x m x 16 cm; 4,5 inch x 6,25 inch); the pdf contains suggestions on how to size for a different e-reader.
The pattern can be worked flat or in the round, the pdf contains instructions for both tecniques. Either way sewing is required.

Materials needed:

• White yarn (needle size suggested between 3 and 4 mm; US size 4)
• Black yarn (needle size suggested between 3 and 4 mm; US size 4)
• 3.5 mm needles (US size 4)
• Stitch markers
• Tapestry needle
• Cable needle (the yarn colour is based on the picture of the white sleeve, any colour can be used)

This project doesn’t require more than 150 meters of yarn. The yarn suggested above is just an example of what you’re looking for, but anything worked with 3,5mm needles works.