Thread the shoes as normal with the two-toned laces. The ends of the laces should be approximately the same length. For example, if you thread a shoe with a two-toned red and blue lace, the red side and the blue side of the lace should be the same length.
Cross one end of the laces over the other to make an "X." Wrap the lace you crossed over the other under the other lace and through the hole formed by the "X." For example, cross the blue lace over the red one to make an "X," and then wrap the blue lace under the red one and through the hole formed by the "X."
Make a loop with each side of the shoelace -- one red loop and one blue loop, in our example -- then cross one loop over the other. This forms another "X," as before, but with doubled rather than single strands. Cross the same color over as you did before, even though it is coming from the opposite side now. In our example, you would cross the blue loop over the red loop.
Pass one loop through the hole formed by this second "X." Again, this is a similar process to what you did with single strands and should be done with the same colors. This means, in our example, you should pass the blue loop through the hole.
Pull both loops gently to snug up the knot.