The bricks were so dry that I had to lay them out like that and soak them with a hose. They were sucking the give out of the mortar immediately otherwise. Anyway, here is how I did it:
Setting out the curve was bit of a pig, though, because the centre point of the arc was inaccessible, being inside the house behind a solid wall. This meant lots of careful measuring to establish the corner, the mid-point, and distance out from the house to the curve every 1500 (5').
Then, out on the lawn, I set up some off-cuts of OSB and a centre-point, and swung the appropriate arc, which I cut out carefully with a jigsaw (I knew there was a reason for owning one!):
I then carefully aligned the template with the marks on the foundation I had set out earlier, and laid a few bricks. The above paragraph covers about 3 hours work!
I since laid bricks around to the steps position, which will be on the midline. No photo, sorry.