Gather a sheet of paper
Fold the paper in half lengthwise
Unfold it
Fold both long edges toward the center crease
Fold the paper in half lengthwise again
Crease firmly along all folds
Fold one end inward to form the kunai blade tip
Tuck or flatten the folded tip securely
Fold the opposite end to create the handle section
Shape the handle by folding small sections back and forth
Press all edges flat to hold the form
Repeat with additional paper if you want a thicker kunai
Trim any uneven edges if needed
Adjust the folds until the kunai shape looks balanced