Step 1:The backside of this paper is completely white.
Mountain-fold over the pink line, it's a little
to the left of the center-line
Then, turn the paper
Step 2:
Fold the edge on the left to the edge on the right,
see arrows as guidance
Step 3:
Valley-fold over this line
Step 4:
Unfold the model
Step 5:
This line is prefolded in the wrong direction (=mountain-fold),
prefold it in the right direction now (=valley-fold)
Step 6:
Prefold over these 2 lines
Step 7:
Make an inside reverse fold over the 3 pink lines.
A valley-fold is almost automatically made over the
2 green lines while you do this.
(All lines are already prefolded, except the pink mountain-fold)
Step 8:
Repeat step 7 over these lines
Step 9:
Repeat step 7 over these lines
Step 10:
And repeat step 7 over these lines.
The edge on the right goes over the edge on the
left, see arrows as guidance.
Step 11:
This is how the bottom of the model looks
Step 12:
Hold the model the same as I do here, with 2 fingers holding
both edges.
Push the piece between the green lines inwards, use the
folding lines as guidance.
Step 13:
Push the top of the model completely flat now, see green lines.
Repeat steps 12 and 13 on the other side
Step 14:
Mountain-fold over the pink line.
Step 15:
Valley-fold over this line.
DONE!
This is a video with me folding a milk carton:
