Moving mods from C drive to D drive

Hi, I am running out of space on my C drive (where the Sims is installed and all of my mods and cc). My D drive (also internal storage) is basically empty so I would like to just move my mods folder here (not the whole documents folder (as I've seen in some videos). I wondered if anyone knew of a way to just move my mods folder to D and have the game communicate with that folder for mods even though the game is installed in C. 

I need a really clear step by step on what to do, an idiots guide basically because I really don't want to get it wrong and I'm not the most technical these days :).

Many thanks!