In this tutorial I simplified the method of pattern making and did it in nontraditional way. I made it because the pattern of this sandal consists only from straight leather straps. I find easier to make such pattern just by attaching paper straps to the last. I taped the last only to make clear drawing of the basic points. As straps of Rihana's sandals reach almost to the knees I just measure the length and width of these straps and buckles on the foot. It's important to know that to be comfortable to wear a sandal with a buckle above the bone, it must be in a distance of 8-9 cm from the bottom of the heel (for size 37 and for each size ad 2-3 mm). Paper strap N2 is in 13 cm from the bottom of the toe. This is the max height at which the foot will easily enter the sandals without adding any fasteners. All straps patterns (upper and lining) are made without any stitches and attached with cement glue. The most important detail for attaching these leather straps to the last is to make the right marks of their location on the midsole.
More info you can find on my blog: MAKING SHOES