update README

README.md

@@ -28,6 +28,9 @@ Install board support package, find instructions [here](https://github.com/mcci-
 Arduino IDE:  
 Select Tools -> Board: -> MCCI Catena 4610.
 
+For the GPS sketch:
+Select Tools -> Serial Interface -> USB + HW Serial  
+
 [Catena 4610 Product Page](https://store.mcci.com/collections/iot-building-blocks/products/mcci-catena-4610-integrated-node-for-lorawan-technology)  
 [Catena 4610 Pin Mapping Diagram](https://github.com/mcci-catena/HW-Designs/blob/master/Boards/Catena-4610/Catena-4610-Pinmapping.png)
 
@@ -58,9 +61,6 @@ Select Tools -> Upload Method -> STM32CubeProgrammer(SWD)
 Arduino IDE:  
 Select Tools -> Upload Method -> DFU
 
-For the GPS sketch:
-Select Tools -> Serial Interface -> USB + HW Serial
-
 To put the board in DFU mode, hold down the boot button while pressing and releasing the reset button.
 
 #### ST-Link