More ideas from José
Striped bag tutorial part 1. Part 2 here http://buscandocomienzos.wordpress.com/2012/03/10/bolso-balon-striped-bag/ The original pattern by Pierrot in English is here http://gosyo.co.jp/english/pattern/eHTML/ePDF/1007/1w2w/29-210-44_Striped_Bag.pdf

Granny Square Striped Bag by Casi Bolso Balón - Created from one big granny square. There's a link to the original "Striped Bag" pattern (in English) in the article under the first photo that includes charts and schematics.

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no need for pattern other than a granny square. then line the inside with a piece of canvas and go to any notions store (Merceria) or to Marshalls, or hobbie loby and by the handle =)=)