How to anchor contrasting color to first stitch in a row?

I'm making slippers in a checkerboard pattern. It calls for knitting 6 and then pulling contrasting color acoss and knit next 6 sitches, etc. It also says to be sure to anchor contrasting color at the beginning of each even row. Never heard the term anchoring before. Does it mean to tie it to the first stitch in that row? Thanks for any help.