How to transfer Lightroom catalog to external hard drive?

My macbook pro is almost out of hard drive space so I'm trying to relocate my catalog onto an external hard drive. I tried following youtube and web guides but I must be doing something wrong. 

My goal is to have all of my Lightroom files stored on my external drive, with just the aplication on my computer. I also don't want the cloud to sync photos, as I would like to keep my work and personal photos in seperate catalogs.

Right now, the Lightroom originals folders are stored on my external drive but the file "Lightroom Library.lrlibrary" is located in users/myname/pictures. When I copy pasted the lrlibrary file onto my external drive and renamed the original file (as per this tutorial: https://www.youtube.com/watch?v=RVfxlbDsSIo) and opened lightroom again, Lightroom automaticaly made a new catalog file in the same pictures folder and began syncing all of my photos from the adobe cloud. If I open lightroom by double clicking on the catalog file from my external drive, the same thing happens. 

What am I doing wrong?