Buy an Adapter Shield. Post a link to the actual item that you have bought.
We can step you through the wiring of a 40-pin e.g. DB5 is #8 on your display connects to #12 on the 40-pin
If you buy the 32-pin Adapter, you just need to check the voltage on pin#1. If it is 3.3V, you can plug your display directly in to the 32-pin socket.
The software is the same for any 40-pin Adapter e.g. UTFT with model ILI9341_16 in the constructor.
David.