How do I thread elastic through a leg band?

I have been knitting a bikini. A lot of it with the help of all of you answering my questions as I go. Anyway, I have one more question. I cannot figure out how to thread the elastic through the leg bands. Here are the directions:

Join side seams.
With right side facing, beg at side seams and using a set of 3.00mm needles, knit up 122 sts evenly around leg opening.
Knit 1 round.
Cast off.
Rep for other leg opening.

Then it says “To Make Up”:
Thread elastic through bands.

I cannot figure out how to thread the elastic through the bands. Am I missing something?

Thanks for ALL of your help!

Put the elastic on a needle or small safety pin (depends on the width of the elastic) and weave it through the stitches on the band, over and under. Unless you make a casing for the elastic…

sue