Import this FREE .MOGRT (Motion Graphics File) into your Essential Graphics Panel or import the .PNG into your Essential Graphics panel. You can then place this Rule of Thirds graphic overlay on top of your video in your timeline. To turn the Rule of Thirds overlay off, click the "Eye" icon on the layer that the Rule of Thirds graphic overlay is placed. 

In the download there are two files: 

(1) .PNG for Adobe Premiere Pro CC 2015 users

(2) . MOGRT file for Adobe Premiere Pro CC 2017 users, you can import this file in to the Essential Graphics Panel.

This rule of thirds overlay is 1920 x 1080, 16:9 aspect ratio.