The final common pathway of any approach to flow is fully absorbed focus. The stronger the concentration we bring to a task, the more likely we are to drop into flow while doing it. While the other paths to flow depend on getting the externals right – the challenge/demand ratio, or finding work that aligns ethics, excellence and engagement – full focus is an inner dimension. The better our ability to pay attention to what we choose and ignore distractions, the stronger our concentration.
Tip: once you've achieved flow several times, recall what that state felt like in your next writing session. You'll achieve it faster.