The edge of the Netted Collar is found on pages 148-149 of Tatting and Netting or page 150 in this version of the book.
What I'm calling the edge began on row 24 and continued through row 29. Because I made a sample and not the collar I'll number the rows of the sample with the collar rows in parentheses.
Fill one netting needle with single thread and one with double thread. Begin using the one with single thread.
Row 1: Net 12 loops into the foundation loop over a 1/8" flat mesh stick.
Rows 2-3 (24-25): Net 1 knot in each loop over a 1/8" flat mesh stick.