Engagement ring during wedding ceremony?

So I've heard a few different ways of how your supposed to wear your engagement ring on the big day. I've only been to about 3 weddings and never thought to pay attention to what the bride does with her ring. I've heard that some people have their engagement ring on their right hand and then put the wedding band on the left during the ceremony, or I've also heard that you just put the wedding band on in front of the engagement ring. I know ultimately it's the brides choice what do to but I just was wondering what other brides plan to do or have seen done 😊