PiTFT 3.5 2.5 touch screen displays adafruit


AdaFruit Source Documentation

Display installation is fairly simple.
If your pi and display already have headers you can just plug it right in, if not there is complete instructions on the adafruit site on soldering the headers and build details.
With the two headers lined up so that the display sits above the entire pi (3 or zero) align the pins so that the first pin on the display matches the first pin on the pi.

Using the pi download and install drivers
cd ~
wget https://raw.githubusercontent.com/adafruit/Raspberry-Pi-Installer-Scripts/master/adafruit-pitft.sh
chmod +x adafruit-pitft.sh
sudo ./adafruit-pitft.sh

After running the scripts you will be presented with two options.
The first will be either using it as a terminal or a gui. I selected No so that it runs the gui.
The second will be the resolution.
This will require a reboot of your pi before the displays the desktop.

If you want to change the resolution (I did), you can do so using:
sudo raspi-config
I did this to set the resolution to 1080 so it matches my TV hdmi.
You will have to hunt through the menu to find the resolution selection, I believe it was under the advanced settings.