Joining a 2nd bll of yarn for a v neck

How do you join 2nd ball of yarn working both sides once dec 1 st at eaach neck edge every 2nd row What is a neck edge and how do you join 2nd ball Thanks New Knitter

To add a new yarn you just start knitting with it. It will be loose at the join, but you can weave in the ends later to tighten it up. If it bothers you a lot you can loosely tie those ends and then untie them before weaving in.