Great pattern!
Here's what I do ......... face the two pieces together, then stab in a pin where they should match.
Just leave it stabbed in and go all the way along, matching all the points that should match, with stabbed pins, including the beginning and ending marks of the seam.
I call this, the picket fence!
Then I clip on wonder clips side-by-side all along, keeping the pickets at right angles all along.
I usually put a pin in the traditional way at the beginning and ending of the row.
Maybe in the middle, depending on the length.
Once all the wonderclips are in place and those two pins, I remove the picket fence.
Next ... go to the machine and stitch across, removing the wonder clips, just as I come to them.
If I have done it right .... it matches perfectly all along the way.
Seldom do I rrrrrrrrip it out .........
And believe me, as I absolutely hate reverse sewing and would remember quite well!