

Use ½ piece of a sheet.

Fold the left and right sides inwards as shown.

Fold from the top side as shown.

Unfold the top side. Cut it slightly from the right and left sides as shown.
Now, turn the model over.

Fold the left and right corners downwards as shown.

Cut the upper and bottom portions along the dotted line. Fold the
bottom portion backwards.

Draw the buttons and your shirt is ready.