Which of the following is an important rule regarding colon usage

Colons denote "that is to say" or "here's what I mean." They make sentences’ first parts not important rather the sentence’s second part contains the important information. Here are some of the rules you could use for colons:

*Colons are uses upon introducing items.

*Do not use capital letters after a colon except if it’s a proper noun.

*Do not use colons after a verb or preposition.

*For independent clauses, especially when the second sentence explains the paragraph’s meaning, the use of colon is preferred.

*After a colon: capitalize the first letter of the first word if it is a complete quotation.