Flexibility sensors are used to measure bending response of flexible materials which are employed in different technologies. They can be produced with easily available and low-cost materials. Its compactness, lightness and low power consumption makes this sensor ideal for manifold as well as any applications needs to monitor changes in shape or bending behavior. In this paper essential steps needed to design a custom-made, longer and cost effective flex sensor were discussed. It was found that selection of resistor, temperature dependency, and maximum possible length are major criteria to be considered. The best resistor which yields the widest range was determined to be 100 Ω with a maximum length of 75 cm. Another important finding of the study was the need of temperature compensation.