Higher education is faced with the question of how large numbers of students can be supported to learn complex skills without increasing teachers' supervision time proportionally and while preserving, or preferably improving, quality. Just practicing skills once does not work. Students need repetitive practice, feedback, and structured support to master a skill. They need to gain insight into what went well and what could be improved so that they can further direct their attention while practicing. However, teachers cannot provide feedback on every practice session of students, as their time is scarce. To solve this problem, an online formative assessment method for interactive and practice-oriented skills' training, Pe(e)rfectly Skilled, was developed that provides structured support for self-regulation, goal setting, feedback, and reflection. This method affords practicing skills repetitively, both individually and collaboratively, at students' own time, pace, and place. In this article, theoretical and practical underpinnings underlying the Pe(e)rfectly Skilled method are described.