[13] recently provided a systematic review about usability studies for wearables: they identified thirty-seven studies in which a substantial heterogeneity in the quality of reporting, the methods used to assess usability, the devices used, and the aims of the studies precluded any meaningful comparisons. Questionnaires were used in the majority of the studies (70.3%; n = 26), which was followed by those who used interviews (n = 17; 45.9%), while the methods of analysis were not reported in over a third of the studies (n = 6; 35.3%). Their conclusion was that usability of wearable devices is a poorly measured and reported variable in the specific field of chronic health conditions. Regarding wearables and their related applications for physical activity monitoring, [PERSON] et al. [14] found in their systematic review that usability was investigated by sixteen studies (14.4%, 16/111), out of which nine (56%, 9/16) used SUS, four (25%, 4/16) used interviews, two (13%, 2/16) used focus groups, and one (6%, 1/16) used observations of the participants completing timed tasks. Three dimensions were identified in relation to assessing the usability, namely (1) the burden of wearing and using the device, (2) interface complexity, and (3) perceived technical performance. Sometimes, usability is intended as derived only from the technical reliability to support the adoption of the wearable device in clinical settings [15]. In their study, [PERSON] et al. demonstrated the accuracy of the measurement of physical activity in the elderly population by means of a smart watch so as to recommend its clinical use but without any usability assessment. The same approach was used by [PERSON] et al. [16], with an acceptance measure being collected through user interviews. [PERSON] et al. [17] performed comprehensive usability assessments with 18 patients with [PERSON]'s disease using a mixed-methods usability battery containing the system usability scale, a rater-based evaluation of device-specific tasks, and qualitative interviews. Usability is also essential to be considered since the design phase of these devices, because it is a basic requirement to match user acceptance of the product-service system, as well as its proper use, the reliability of the data measured by it, and the motivation and engagement of the overall approach or service that the system implements [18; 19]. For example, in health-monitoring services, in some cases, it is crucial to wear a system in a specific body position to carry out the measurement with a dedicated procedure and receive feedback on the data quality to ensure that the entire process is complete and correctly executed. The semi-automatic monitoring of blood pressure with a body-worn cuff at the wrist represents a typical situation for this case. These studies have reinforced the idea of the need for a standard, multifactorial, and integrated approach in usability assessment. In light of these findings, in tackling the importance of these factors, the assessment of the usability of a wearable technology needs to be carefully planned and prepared though a structured approach. Users, the target application or function, and its specific requirements, as well as the morphological category, drives the development of a well-designed protocol. This paper aims at providing a structured and standardized process to define a usability protocol for wearable systems. The aim of this paper is to propose a structured methodology to conduct usability analysis with wearables and to propose a set of reference questionnaires and charts to be used in experimental tests; this could lead to a common grid for usability assessments for further studies in this field. In Section 2, the author presents a segmentation of usability assessments in five phases and a decision tree supporting the evolution of the process. This is the most relevant section from a methodological point of view.