Player specific control on client screen architecture?

Hello there, I'm trying to build a turn based game where clients will execute turns on their own device. The Server displays the playing field, and the clients should display some client specific stuff like Cards and chat. I'm currently using RPC to execute commands on the client, and the game runs in a script called ServerScript that currently also draws a gui. If possible i would like to be able to draw the gui of the client in a seperate class but i'm having trouble getting that to work.

The question in short: What would architectureally be the best way to achieve what i'm trying to do? How can i split server and client logic better?