Cognitive load theory (CLT) is concerned with the design of interfaces that allow users maximize their working memory when problem solving. This includes eliminating any subjective mental load that may be imposed by the instruction interface. Augmented reality (AR) is fast gaining application in areas of education, military, business and medicine with new AR applications developed daily. Despite its wide application little has been done in the area of design guidelines for AR user interface and the evaluation of its effect. This is necessary so as to ensure that users are not burdened by the format and amount of information presented in the augmented view. This work - in - progress aims to propose a framework for designing AR user interfaces that imposes reduced subjective mental workload on users. Particular attention is given to highly cognitive tasks such as simultaneous interpretation. This research work will concentrate on presenting the novel guidelines for the user interface design.