This bag is worked from the base up, entrelac style. Starting with a length of chain for the foundation, three regular entrelac squares are worked along this chain for the base. The remainder of the bag is worked one square at a time, joining as you go, from the base.
The photograph illustrates the bag made with a 100% acrylic, double knitting weight, yarn that has the appearance of cotton.

I recommend any double knitting weight yarn, but cotton or cotton blend yarns would be best.

Although this pattern is written for Tunisian crochet, it is possible to work the whole item with a regular, straight crochet hook. No need for a special hook. A basic knowledge of Tunisian crochet is helpful, but not essential as stitch instructions are included in the abbreviations section.