If you want a semi-fitted liner and have a bit of difficulty seeing it, turn the basket over and use the outside as a basic pattern. By draping your fabric over it, you will see how it needs to fold, bend, drape. This might help you see the tube and flooring you will need to measure. Reminder, the inside is an inch or so smaller, so think about that and you can adjust the seam allowance to compensate for that.