Changing yarn from border color to main color

[1dove]

I am knitting an afgan that has a border all the way around. The border color on the sides of the afgan is 10 stitches, then the main color and then border color for 10 stitches. Will I need to cut the border color each row and how do I make it look even all the way around. Would I need to knit the border seperately and then somehow put it together with the central body of the afgan? I am really confused as to how this works and the pattern does not give any instructions as to how to do this. Please help. Thank you.