This course presents the fundamentals, lessons learned, and challenges of developing research in Human-Computer Interaction (HCI) with older adults interacting with the Web. The course is intended to be applicable to different research questions, but examples will be provided around a research developed in the context of computer anxiety. Computer Anxiety, can be characterized by fear, apprehension, and discomfort in using computing systems. Despite the ubiquity of technology, some individuals still experience significant levels of computer anxiety, particularly in scenarios where computer use is mandatory. The proposal is based on empirical experiences conducted over five years exploring cognitive, emotional, and social barriers in the use of digital technology by older adults. The goal of the course is to share with the HCI community applied and adapted methods and materials, in addition to addressing ethical concerns throughout the whole research process. Course participants will learn by simulating how to design and run a research study with older adults in real contexts of use. Hence, the relevance of the course lies in encouraging attendees to think about the problem of performing user studies with technologies involving people who may deal with barriers, even before they actually interact with computers.