HCI is a swiftly advancing field, with insights gained from new studies published year round. Many studies target specific user groups that may be difficult to access, time-constrained, or small in size. Such groups may include older adults, individuals with disabilities, children, or people from diverse cultural backgrounds. In such contexts, we aim to illustrate how to adhere to guidelines, ensuring the delivery of safe, well-tested interaction methods and tailored approaches by following responsible research practices. To facilitate this process, we present our approach of four phases of multistage user studies, namely (i) lab studies, (ii) static field studies, (iii) mobile field studies, and (iv) remote online studies. We also present use cases, which evaluate the methods and tools involved in each phase and provide guidelines for selecting an approach.