1) Download GTmetrix for Wordpress, install it on your wordpress, Register and get the API Key. Then run Front End test 2) Update your current Wordpress Site This is Very important part of the optimization; in case something goes wrong with your optimization you have backup. My recommendation is UpdraftPlus Wordpress Backup Plugin

Download the Plugin and activate it and then check Include the Db and Include any files and then click Backup NOW. When you get the message Successfully backed up and you should see this.