Torch is super easy to install. The first step, is to head over to the Chrome Extension Store and run a quick search for "Torch". Here's the link to save you some time: https://chrome.google.com/webstore/detail/torch-sales-intelligence/gkniokdpjjndfjbemndmjckjmclnimge
Once there, click the blue "+ Add to Chrome" button, then click "Add Extension". Then head over to your email.
Once in, you should find this popup in the bottom of your screen. Just hit the "Connect Gmail" button and then hit "Allow" when faced with the permission rights screen.
Once finished, the Torch dialog box will be shown in the top right corner of your screen.