It's a very cute pattern
so no wonder you want to do it.
The poncho is knit in the round so as you're knitting from the needle in your left hand to the needle in your right hand you purl through 24 of the 26 purl sts and then purl the last 2 together before working the chart. That's purl2 tog at the end
of the purl section. The same is true for the second section of purl sts. Looking at the outside or public side of the poncho, the left side is the left edge of the purl section as it faces you.
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