To keep the floppy next plank aligned with the previous attached plank, I made a small device with a slot in the center that fits snugly over the two planks. The wooden prototype was cut on a table saw from the end of a 2x4, but was not useful because it stuck to the glue on the strips. I transferred the dimensions to a 3D printer program and printed out a dozen of the devices in plastic which does not adhere to the planks. This simple device speeded up planking and reduced my frustration level.
How about a photo?
For those without 3D printers, a layer of packing tape will prevent adhesion.
Laszlo