What was your source for this crocheting project? Online Photo or Website Name of website or photo Reversible envelope evening bag Link to website or photo www.interlockingcrochet.com/the-book.html What advice would you give someone starting this project? Technique is really interesting. The book has some errors that are corrected on the website here : http://www.interlockingcrochet.com/the-book.html It is a wonderful stitch repository and the directions, supported by videos on the same website, are excellent (you definitely must look at the video for the "dcib"). This creates a fully reversible item with two sides of the same pattern or different ones. Lots of fun, just do it !