Inspiration

The idea for this cushion cover popped into my head during my yoga class last week. It a variation on the work I have been doing recently on fabric gathering but simplified. This got me thinking about inspiration and new ideas.
Where does it come from and how can we tap into it everyday. Over the years I have read many books on this subject and the most commonly mentioned point is to just get started with a project and ideas will slowly began to flow for new work. Keeping a sketchbook of ideas is also invaluable.
Personally I have noticed that ideas will come to me when I am not actively thinking about my work like during yoga last week.
Sigmund Freud once said "When inspiration doesn't come, I go halfway to meet it"
Where or how do you find inspiration?