@veevee_24 you can arrange the strings like seen in the pattern. The margin will turn multicoloured automatically, if you do regular triangle ends. Just do what you need to do for regular triangle ends and not for single-colour triangle ends.
@emmagilll I cut 5 black strings (190cm each one), 1 light blue (190cm), 1 dark blue (190cm), 1 white (190cm) and then I folded them in half and made a knot