The awen (a Welsh word) is invoked by Druids in ritual, usually by chanting it. This is one of the traditions we owe to revivalists, not to ancient history. However, the experience of flowing inspiration is something that can and does happen – during periods of creativity, but also sometimes when performing.
For me, it’s a sensation of being completely taken over by what I’m doing and being able to do it in a totally different way – with more drama, intensity and depth than usual. On rare occasions, it’s had some very odd effects indeed. I recall a ritual when three of us spontaneously improvised music together, and another ritual where I re-wrote one of my own songs as I went to better fit the situation. I had no real memory afterwards of what I’d sung.
Awen is something that turns up when it does – it cannot be summoned by force or will. You have to be open to it, welcoming of it, ready for it, and also perfectly able to keep going if that other level of magic doesn’t happen. Sometimes it comes as a trickle, adding a sparkle to what you were doing. Sometimes it’s a tidal wave that will wash you away.
When it comes, it is best to let that flow direct things rather than trying to control it. If you want the kind of magic controlled by will and personal intent, this is not something to try and court. If you are willing to be a flute the awen can play its own tunes through, it may do just that.