You can get started easily by evaluating on of the example projects found here.
The HelloWorld project is ideal to start with. You'll need to have a LoRaWAN connected Gateway for receiving the 'Hello World' message.
If you prefer to evaluate LoRa to LoRa communication or don't have a gateway set up, the LoRa to LoRa project is a good starting point. For this project, two OTX-18 modules/devkits are required.