Knitting a row when yarn is in the middle?

Hello all -

brand new to this forum. And a new knitter. I am attempting this pattern: http://pringelinghobby.files.wordpress.com/2012/08/babydress-eng.pdf

I have completely finished the yoke and am at the under arms part. I slid the stitches from the right front to the left needle and now I am very confused about how I am supposed to purl a row when the yarn is in the middle of the row. Can someone direct me?

Thanks!
Jessica

You should use a new strand of yarn to work the 54 stitches into one row. Cut the yarn that’s hanging in the middle and just start purling from the edge.

thank you!!!