In this task the focus is on physical knowledge about the world. Given the provided goal task in the input, describe a process that would lead to the asked outcome. This process often involves physical motions with objects, such as moving them, arranging them in a certain way, mixing them, shaking them, etc. 

container
can't be covered in a  receipt 

To clean old CDs that are scratched and dirty so that they continue to work,
rub the CDs with toothpaste, a clean rag and cold water afterwards.

How to hang lights without showing the hanging mechanism?

When placing up the lights drape them over small, black hooks which will be undetectable to the eye at night