How to make a postcard from a piece of cardboard with a length of 148mm* 100mm?

Put a stamp on the upper right and write the recipient's address on the lower right (just copy the address provided by the other party completely, but pay attention to the translation of the country name into Chinese); Write the sender's address in the upper left corner. Students who want to write are advised to reduce the font size by one yard), and you don't have to find the zip code. Write it in the red box in the upper left corner of the postcard in the lower left corner.

International airmail postcard 4.5, land and water 3.