None for using, but please be sensible whenever thinking and applying a model of thought. It's all abstract and in that experiential space - nothing is perfect for everyone in every context.
This is a "chat through" session with a coachee or a group
30 minutes and more, dependent on the group's size and engagement
Read the wikipedia page http://en.wikipedia.org/wiki/Flow_(psychology) and be sure to click on all the segments in the picture which are links to a bit more detail which you will need to know and understand.
Step 3: And as the picture is quite self-explanatory, especially having read the background reading available on wikipedia and other sources, the conversation is quite easy to have. I ask for examples of what tasks the coachee or the group members perform that are Low in Challenge Level, and Low in Skill Level.
2.The person must believe that they have a good balance between the perceived challenges of the task and their own perceived skills - they must be confident.
3.The clearer and more immediate feedback the person receives whilst engaged, helps the person get into this "super state" and then stay there for longer
Flow psychology provides a great tool for explaining the enjoyment people report when they embrace modern/agile software engineering practices like Test Driven Development, Pairing, Collaborative Design and more.
I have not read Mihaly Csikszentmihalyi's book Flow: The Psychology of Optimal Experience yet, but I find the graph he drew above incredibly useful when talking to people about their experiences of work - what they have really loved in the past, and helping them understand what they are experiencing currently. This tool helps provide some motivational energy to help people make a decision to try something new.