Help! How do I carry second color yarn when knitting rows

I am knitting a sweater and it calls for rows of two different colors. Each color goes four rows before switching the color. They alternate the entire length of sweater front. How do I carry the second color yarn? I don’t want the cut and start each section. Is there a way of hidding the second color and still carry it along? Are there any hints, instructions etc…? What is this called? :??

It’s called [I]“carrying the yarn up the side and knowing that seaming will hide it.”[/I]

Seriously, just bring it up the side. You can make sure that you bring the yarn you’re using under the one hanging to help hold it to the side, but for a sweater, the seam [I]will[/I] hide it.