what if i dont flash any image?

The original image or OI is a fully functional image but it is very very basic and not as customisable as the Third party images.

put ther stick in the front usb , power the unit off at the switch , wait 5 secs and power on at the switch on the back again then press the power button on the front of the box when it says update then sit and wait

Ensure you have downloaded the right image for the correct receiver.

Installing the wrong receiver image will brick your machine and it will be a right pain to unbrick it.

Always check and double check.

There are some fantastic backup images including blackhole for you in the backup part of the forum, 99% of the hard work has already been done for you in these images. Makes it far easier if its your first time.

you can use this tutorial for flashing the receiver, substitute the image for any of your choice.