The Big bow bag pattern is best for advanced beginners. The following techniques are used in both patterns (US terminology): half double crochet, slip stitch (to attach panels), half double increase and decrease. For the Big bow bag, you'll be using a triple strand of yarn for most of the pattern.
Measurements: ✧ Big bow bag (excl. straps):width 36 cm (14,2"), length 24 cm (9,5")