I wrote how to do a basic Arch Linux installation on the Thinkpad T450s in this article. I will now describe what to install and configure next to be able to really use it. The desktop environment I'm using is GNOME so some instructions will be specific for it.
Until now, I was using an Asus laptop that I had to buy quickly because I needed a new one for my work. However, the laptop wasn't very Linux-friendly and as I had enough with the problems I was encountering, I decided to change for a Lenovo Thinkpad T450s. First time of my life I can say I'm satisfied with a computer! I will give you also the installation guide I used for ArchLinux.