What principles should be followed in writing Spring Festival couplets?

Writing Spring Festival couplets should follow the following principles:

1. Use red paper. Because Nian is a fierce beast, it will come out to hurt people every New Year's Eve, but Nian is afraid of red, so every family hangs red things on the door on New Year's Eve.

2. The fonts commonly used in Spring Festival couplets are: regular script, official script and running script. Others, such as cursive script and seal script, are not suitable for writing on Spring Festival couplets. Regular script is dignified, official script is beautiful and running script is elegant. These are all calligraphy styles that people like.

Spring Festival couplets are popular things, so you'd better understand them, otherwise you can only enjoy them yourself.