I have tried a search as Im sure it has been done to death but cannot find an answer I can understand, I am not very techy so can someone please tell me in simple language how to update my satnav to latest map. I have been to the Skoda Portal, entered my VIN and can see i have to download file to my PC, its the next bit I am confused about?

Do I need to use the original SD card from the car to copy files, how do I do it?
Grateful for newbie support