How to fold self locking origami gift bag (Makoto Yamaguchi)

Bordered origami bag designed by Makoto Yamaguchi. I used a 15cm x 15cm gift wrap paper from Oliver Bonas. The finished size is about 6.5cm x 6.5cm. This cute self locking gift bag is perfect for little present.
Step-by-step diagram instruction from: 両面友禅千代紙 by Toyo. ふちつきバツグ 折い図指導 . 作/やまぐち真 (inside 青海波 origami paper pack)