It is extremely important to root the extensions to make a seamless install.
Be sure to wash the extensions prior to applying any color.
Using RedKen Gels and 10 Vol apply a line of color to the base of the weft and pull the color thru with a brush on both sides.
Then weave out some of the hair within the wefts for the low lights.
Rooting the extensions gives your client the most natural look.