"vorher", "zuvor" and "früher"
I often use these adverbs in the wrong context, what I would truly appreciate from any German native speaker is an explanation on when exactly to use each the aforementioned attributes, when talking about an event that happened previously.

Ex: "..Das, was ich vorher/zuvor/früher erwähnt habe.." on this example, what would you recommend me to use and why?

Question

"vorher", "zuvor" and "früher"
I often use these adverbs in the wrong context, what I would truly appreciate from any German native speaker is an explanation on when exactly to use each the aforementioned attributes, when talking about an event that happened previously.

Ex: "..Das, was ich vorher/zuvor/früher erwähnt habe.." on this example, what would you recommend me to use and why?

Answer

"Vorher" and "zuvor" are pretty similar to each other except that "zuvor" is more formal. They are used for events that happened not long ago (for example: Das, was ich vorher/zuvor erwähnt habe,..). "Früher" is more likely used for events that happened a long time ago, for example when you're talking about your childhood.