There is a little trick for short selling.

Don't short a single currency with a heavy position!

Suppose you want to short a position of $40,000, find 4 or so relatively weak ones, short each for $10,000, which is safer than shorting a single currency for $40,000.

For example, if you short Wif, it may fall more in a certain period, but the rebound is also stronger than others;

Some currencies do not fall quickly but have been very weak and have not rebounded much, which will be more comfortable when spread out comprehensively.

To observe the performance of different currencies, I usually take a small long position in Bitcoin to see how other currencies compare to Bitcoin at this time.