What is "tie on" as opposed to "cast on"

:?? I have an instruction card from The Little Box of Scarves for a self-fringing scarf, using 4 different types of yarn that I have to TIE ON leaving a tail at the beginning & end of every row.
I contacted the company, but they were of no help to me.
Can anyone help?

Does the scarf show fringe by any chance? Sounds like maybe they’re trying to get yarn hanging off the edges on purpose.

Yes - you are correct. It “self fringes” -
(Due to copyright laws, I cannot be too explicit .)

First row: cast on xxx stitches, knit across, cut yarn, leave tail.
Rows 2 thru 8 : TIE ON leaving a tail, knit across, cut yarn; leave tail.

(Each row requires that I TIE ON a different type of yarn, i.e. Flash yarn,
Bubble yarn, Aura, etc.)
My problem is that I’m not sure of how to TIE ON .
Should I TIE the yarn (by using a knot )to the previous row?
Thank you for your response.