If it is a fence-type anti-theft door, then the couplet needs to be affixed to the wooden door, because the outer layer of the anti-theft door may not be firmly affixed. If it is a fully enclosed anti-theft door, it can be directly attached to the anti-theft door. Otherwise, if it is attached to the wooden door, the ornamental value of the couplet itself will be lost due to the obstruction of the outer anti-theft door.
Notes on posting couplets during the New Year:
1. If someone in the family dies, then according to traditional Chinese customs, couplets cannot be posted within three years.
2. Because both sides of the couplet are symmetrical, be careful not to paste them backwards.
3. When pasting the word "福", you can paste it upside down. "福下" is a good sign of the homonym of "福来".