I'm making the Brea bag from the Berroco free pattern section. I'm working the gusset and I don't understand this section:
Inc Row (RS): Work 1, M1, work to last st, M1, work 1 – 10 sts. Work 7 rows even, then rep Inc Row, working incs into Moss St – 12 sts. Mark beg and end of last row. Work even until piece above markers reaches from right top corner of bag back around outer edge to left top corner, end on WS. Mark beg and end of last row.
What do they mean by "mark beg and end of last row"? So I've got 12 stitches on my needles, for what purpose am I marking it? And then why would I "mark beg and end of last row" again? Do they just mean to put waste yarn or a lifeline or something on the row I just finished so I know where it is?