Dielectric Elastomer Actuators (DEAs) are recent type of smart materials, which transform electric energy into mechanical work. They show impressive performance as soft actuators. Capable of multidirectional actuation, large strain and high energy density, they become new references when developing soft artificial muscles. Even though challenges such as low generated force and high actuation voltage requirement still exist, this technology shows a great potential. Several factors influence the DEA performance, such as the material selection, prestretch, preload, actuator configuration (layers, dielectric thickness, geometry). In this paper, a model and its experimental validation are presented in order to identify and evaluate the main factors, their interactions, as well as significance for DEA performance. The proposed study is based on a design of experiment (DOE) approach to model the different behaviours and interactions between those factors. Three main factors having a significant interaction have been highlighted and a discussion to optimize the DEA performance is presented. This study may provide guidance for the design of high performance DEAs.