把塑料环外翻。 把盖子滑到环里去。 根据需要调整环刺。 钦佩你的作品吧。

I'm interested in that, but I only have a few mins. Can you give me at most the first 500 characters of a detailed explanation in English about that?
Use your fingers to flip the plastic ring so that all of the "spikes" or pointed grips face the outside.  Push on the inside of the ring on one side using your thumb.     Once you manage to flip the inside out in one spot, it should be easier to gradually ease the rest of the inside outward.     Note that the pointed grips may "bite" or pinch into you slightly as you work. Typically speaking, though, the edges are not sharp enough to cause any cuts or wounds.    Wiggle the ring over the outside