How to put half a rhinoceros blade in Jishi's old razor?

The steps of clamping half a rhinoceros blade with an old razor are as follows:

1. There is a button on the handle. Press the button with your thumb, and the plastic on the tool holder will automatically fall.

2. Replace plastic with a blade. There are three clips in the middle of the handle. Just aim one of them at the concave place opposite the blade and push it gently.