Soft actuators have been investigated for robots that interact with people, such as industrial robots, entertainment robots, and medical robots. Although soft actuators have been utilised in several applications, design tools that can assist in the effective and systematic design of actuators are needed. This paper focused on the most common soft actuators for bending motion, the Pneumatic Networks bending actuators. Paper presented a survey on the effects of changing the dimensions on the soft actuator and its cross-section shape on the soft actuator flexibility and the forces generated at different applied pressures. This survey can be used to optimize the dimension ratio for the soft actuator and the cross-section shape. Furthermore, this paper analyzed the possible reasons for the dimension change effect. The performance of the bending soft actuator was evaluated using ABAQUS/CAE software simulation models to provide quantitative insights into the actuators' behaviours. Thus, this paper provided a lot of insights that can be used to guide and accelerate the soft actuator design process to create strong and flexible Pneumatic Networks bending actuators. Using the paper insights outputs, a soft gripper was designed that can grasp many complex objects without needing any modification in the gripper shape. To show the proposed actuators' capacity to do complicated movements and expand their applications, a completely soft hand was created that can mimic the mobility of the human hand as nearly as possible, and this ability was verified using hand sign language settings.