Plater and evlui nameplate help

im using a gavel of the first arbitor. saw a way to highlight the border with weak auras. the guy on youtube vid said plater can be used to make the nameplate of chosen npc bigger. how do i do this? also saw someone say you can use elvui nameplate section to control size of nameplates. followed those instructions but it doesnt work. saw it was an earlier version than one im using now. for making soul fragment nameplate bigger.

I’d suggest posting this on the ui and macros forum but contacting the addon developer would probably be better. This may already be addresses in the developers comments section on their web site.