Once contact was made I got to choose what day DPD collect it and an email to print a sheet with repair number etc to put on outside of box.
The responsibility is all yours for packing it up, I have original box, but have seen people with damaged items which don't get compensated if it's deemed the packaging wasn't good enough.
If you don't have any DPD bring a box and bubble wrap, as was the case in a damaged item that didn't get paid.
Samsung strongly advise photographing item before shipping as proof of no damage. As above, they say DPD box used isn't sufficient for claims, yet use it if packaging required.
Luckily I kept the box and even the bag over screen protection.
I am worried about it all, but still hoping it turns out well and sharing the journey.