Start collecting every polythene bag that you get, Fold them properly and then put all these bags in one polythene bag.

Simultaneously keep on putting polythene bags in one one bags. Finally put all these tied polythene bags in one Large polethrne bad to get the cushion cover shape. It will automatically turn out tobe very sft and fluffy. I have put it into a big black waste polythene, cut or folded the edges by stapling it or you can apply transparent tape. Finally take a simple cushion cover and paint it with Acrylic Colours and put it over your polythene cushion.