Ugg Kids Classic Ultra Mini BootSize Guide: If you're feeling uncertain about which size is the best for you, please measure the length of your foot and add 5mm space, then compare this to our insole size guide (the end of the size options) and find the perfect fit. Please stand on a piece of paper, mark the top of your top and the back of your heel and then measure the distance between these two points. This is going to give you far more precise and accurate measurements. It would