I don’t instantly sign a card the moment I get it (if that matters?) But I’ve been having a hard time signing my new current account card, I had to go over and over and over because it would barely take any ink from my pen (Parker ballpoint blue ink). It seems to have a different material from the prepaid card?
Now it looks smudged and ugly ;(
Anyone else had difficulty?
Mine was fine, with a regular budget Bic black ballpoint.
Ultra-fine Sharpie is the best 
Yep. I use a Sharpie to sign the backs of cards. Biro is a waste of time. Can’t be seen easily.
+1 for using a Sharpie! (Other permanent markers are available)
This just reminded me to go and buy some Sharpies from Amazon…
I live in an area where it is possible to get Prime Now if you so desire so everything will come at least next day…
Amazon is obviously suffering after Black Friday as they’ve given me a 3 day delivery time for a set of pens! 
Sharpies are available, here
https://www.amazon.co.uk/dp/B007QU7VIQ/ref=cm_sw_r_cp_tai_xRUgAbV1803X8
for signing debit cards:
Do people still sign cards?
No NOT orange to sign a Monzo card It is not bloody orange it is Hot CORAL
Just as a quick tip, if you intend to sign your card, it would be best to do it the moment you receive it. 
Attempting to sign the card after it has been in an ATM or two becomes near-impossible as the signature strip becomes sealed. This process helps to stop your signature from being erased but has the side effect of making it difficult to write over. 
Well this is new to me. No wonder I always have trouble signing my cards. 
I sign my cards with ultra fine sharpies but, unfortunately, I do not use a wallet. That means the card is loose in my pocket and over time (this is since 1st August) the sharpie smudges and fades. Still looking for that perfect pen… I hate biros!
Do you need to sign cards? I haven’t bothered for years, since I don’t sign for transactions I really don’t see the point.
Yes, because:
I suppose it might make the card technically invalid as far as the rules go, but I find they work fine anyway. If my card were ever stolen I’d cancel it, though I suppose if the thief signed it and got away with a transaction the bank might use it as an excuse not to refund it. That might be reason enough I guess.
As for signing for things, I don’t. Haven’t been asked to sign for a transaction for years now. Are there places that still do that in the UK? My experience in the UK, Germany and Japan is that it’s chip and pin, contactless or no cards at all. Maybe if I traveled in the USA a lot, I think they still sign for transactions a lot.
I had no problem signing my card… maybe it’s because I’ve got a white core card, perhaps the hot coral core cards have a different line for signing? I believe they come from different suppliers (The Coral Core!)
I’m ashamed to admit it, but I have a favourite pen. I’ve found it worked perfectly on my hot coral core card.
And my favourite pen is a Pilot V Ball 0.5.
I don’t sign any of my cards, first off I prefer the pristine look of a brand new, untouched card, and second I don’t do insecure magstripe transactions anyway, always chip & PIN or contactless. Never had any merchant question it either.
I sign them but I don’t remove the sticker on the front.
I dislike the idea of someone getting my signature if they steal my card! But after a while I reluctantly sign it because I should, guess I left it too long 