Dial the Call Before You Dig number prior to excavation, for safety's sake.
The first step in excavating for the mower strip is to plunge a spade, lawn edger or knife down into the ground, right along the sides of the concrete pavers. A garden spade probably works best for this; but lacking a garden spade (as we did; thus the lawn edger in the picture above), any sharp blade with a straight edge will do. Just go down a few inches (you don't have to establish a precise depth yet).
Now that the exact course for your mower strip is marked and the excavation has begun, you can set the concrete pavers aside again.
On Page 6 we finish the excavation for the mower strip....