Do not cut color not in use

Hi Guys! Am new to knitting, and am trying to start a pair of arm warmers… The pattern uses two different yarns… The directions say " Do not cut color not in use, but cary it up the side of the work." I realized I have no idea what this means! How do I start this thing? At what point do I introduce the second yarn? From the beginning? Would really appreciate some help. Thanks

Introduce the second yarn when you need to use it and not before. Just start working with it leaving a tail of it to work in.

On the color you were using that it said not to cut…every time you come back to that side of the piece where the yarn you are not using at present is hanging, do this. At the beginning of the next row as you continue with the second color, run the yarn under the hanging color before you do the first stitch. That should cause it to caught in at the side.

Thanks… Ill have to play with it a bit…