The younger the better I say. They will be able to get used to you handling them and clipping their claws. When I got Miggy and Petal, both 2 years old, they had never had their claws clipped. You'd think I was murdering Miggy for all the noise he makes now when I clip them. I have to wrap him up in a towel to do it, but it's over very quickly, thankfully!
I buy my soft claws at thecatandkittenstore.com. I can get soft claws there cheapest I've seen, plus free shipping. It's cool.
You can also get them at Petsmart for $20. Try to get them from your vet though first if they offer them cheaper. Back at my old place, I could get them for $15.
Also, some vets will put them on for you. The low cost vet at my old place charged $5, but that particular cat put up so much of a fight I had to pay $25 more for anesthesia. And that was the vet place he liked the most.
I was considering these for Grayse, and I spoke to them at the vet's office. She said that you had to be really careful when putting them on. She said that if the glue gets on the skin, or if the nail cap is against the skin, that the cat can get a nail infection.
Just wanted to mention that, because I was planning to buy them until I realized that they could cause another problem if not applied properly
Saturday will be the big nail clipping and capping day. Our Siberian kitten is 12 weeks old., hopefully a good age to start. Also thank you for posting about possible infection. I'll keep an eye out for any problems.
Why don't you just stick to claw clipping and lots of scratch posts before you try the soft claws and see if you actually need them? Why put yourself - and you cat - through the expense and hassle if it's not necessary. Is your kitten being very destructive or aggressive?
Im a bit concerned about the nail caps after my brother noticed that pink nail caps were being found is his cat's poop in the litter tray, instead of on his cat's claws ! I know they are non-toxic but his cat was obsessed with trying to bite them off and when they eventually did come off, swallowing them.