Using 'Type I' paracord, I spent over an hour on the one pictured below by tying, untying, retying, over and over so that I could get 10 feet of cord into it and have the finished lanyard's total lenght at about 6 inches. I started with a set amount of 10 feet plus about 3-4" extra that I usually trim off it there's room as I finish.
I had to figure how many inches to start tying from the center(4"), how long to make the first set of cobra stitches/Solomon bar/Portuguese sinnet(2"), then overlapping those 3 more times and still have enough left for a finished tail end with a lanyard knot and a doubled granny knot(1.75" long after tying them), and have the loop on the top for attaching it to the knife(1.75" which is long enough to fit thru a lanyard hole and still have room to loop the lanyard body thru it on an average pocket knife, it appears long when just looped onto a split ring like on the SAK).
That kept the finished lanyard at about 6 inches. I have a tape measure handy, but I don't measure precisely as I tie. I mostly just tie/untie until it looks ok to me. I only know those measurements after I've finished, and these only work for that sized cord.
The Swiss Army knife is a Victorinox Ranger.