Color 1is the main color which will be the top half of the pants. Color 2 n Color 3 will be the colors that will be used on the pants leg. If you want the pants to be one solid color then just choose the same color for all options if you want the pants just to be 2 colors then for 2 of your option choose the same color for example you want the ain color to be blue and the other color be white for color 1 you will choose blue n for color 2 n 3 you will choose white.  
 
PLEASE NOTE:the sizes goes by what the child wear not by age since this is crochet clothing. For example the baby is 6 months but wears 0-3 in clothing then you will need to get the size 0-3.