Google Glass is a new personal computing device that employs an over-eyetransparent display together with voice-control in order to offer audiovisual informationto the device's users. Glass is also a new mediated-reality platform,fundamentally different from common computers and smartphones, and theavailable Glass application (Glassware) design guides do not fully cover human-computer interaction issues that are imposed by Glass' characteristics – issuessuch as optimum information density, use of colourization and positioningto separate information, optimum amount of discrete entities on display, and theuse of iconography. By combining existing guidelines for Glassware UI designwith past research on human-computer interaction and psychology, those issuescan be addressed and can lead to additional design principles. To evaluate theefficacy of such combinations within the technical and design limitations imposedby Google Glass, a set of UI mock-ups for fictional Glassware is createdand used in multiple surveys to acquire data on human response to those combinedfactors. During the study, it was determined that factors including colourization,element positioning and use of icons have a definite effect on user perceptionand preferences, whilst factors related to information density andamount of discrete entities on screen are less relevant. Additionally, supportingevidence was found in relation to the assumption that utility is more importantthan functionless aesthetics. As a result, a UI design guideline set was formulatedthat can be used to supplement existing UI design guidelines for GoogleGlass and similar over-eye transparent-screen devices.