Since ribbons are rectangular in shape, you cannot simply braid them as you would your hair. Ribbons cannot be pulled too tightly while braiding because they will start to fold over and lose their shape. But there is a braid called the "two element ribbon braid" that will give your ribbon a braided look without compromising the ribbon shape or structure. When first trying this braid, choose a stiffer ribbon, like grosgrain, as stiffer ribbons hold their shape better.
Hold your first ribbon in front of you, and fold 4 inches of ribbon over to create a loop. The 4-inch tail should be underneath the loop formed. For clarity purposes, lets say the two ribbon colors you're using are black and white, and the ribbon used in Step 1 is white.
Fold 4 inches of the black ribbon over to create a loop – like in Step 1 – with the 4-inch tail being behind the loop formed. Thread the black loop through the white loop.
Insert a straight pin into the white loop right against the black ribbon. This will hold the white loop around the black ribbon tightly.
Fold the length of the white ribbon to create a loop. Slide this white loop through the black ribbon loop.
Pull the length of the black ribbon to tighten the braid.
Fold the length of the black ribbon to create a loop. Slide this black loop through the white ribbon loop create in Step 4.
Pull the length of the white ribbon to tighten the braid.
Continue to repeat Steps 4 through 7, alternating colors, to create the entire ribbon braid.
Fold the length of the black ribbon to create one final loop. Thread the end of the white ribbon (unlooped) through the last black loop, then pull on the end of the black ribbon tail to tighten the braid. This will securely close the braid.
Tie the white and black ribbon tails into a knot, then cut off the excess tail ends with a pair of scissors.