I will explain you how to make 3d paper airplane
Step 2: Step 2
now cut the square paper with scissor in four equal pieces.
Step 3: Step 3
that all four corners will meet at the centre of the paper
as shown in the figure.
Step 4: Step 4
-now fold the four pieces
as shown in the figure 1
and fold as shown in figure 2
Step 5: Step 5
now fold the third piece like shown in figure 4
base ready when you see look
Step 6: Step 6
now take a four piece make it same as front portion
and do as shown in figure looky
(by lifting corner of the last fold)
Step 7: Step 7
now assemble this four part as shown in figure 1.1,1.2
this four pieces can be interlocked in each other easily without any paste because we can use corner of the pieces to fit in each other.
thus the 3d paper airplane is ready!!!