Does anyone know where to get those kitten ID bands you put on them when they're first born? I was thinking of making some with felt or ribbon, preferably something that gives a little and can be adjusted when they grow.
Ta in advance

I would not use ribbons or bands. Kittens get injured from getting their mouthes or a feet caught up in them or get them caught on something.
I think a few breeders use hairties, the ones without the metal clip part though. If you know what I mean. I use them (as hairties) and you get about 10-15 in a pack really cheap just from the supermarket. They are really soft and the cats love them.
Jake's breeder used nailpolish on their nails to determine which kitten was which but I've heard that it comes off really quick and doesn't work as well as other methods.
I've heard of the nailpolish too, not sure if i'm a fan of that tho. Yes the cats definitely love hairties, I often find mine half-chewed in strange places!
Soon enough, they can be told apart by sex, color,pattern, weight. Before that, if one must tell them apart and cannot do it by look and weight - and there is not much reason to do it, clip some fur on a foot or leg. Kitten 1 would have nothing clipped, Kitten 2 would have the left front foot clipped ... Better than a strangulation risk - and yes, some breeders do it without ever having had a problem.
My brother used nail polish on top of his golden retriever's puppy heads. It was kind of ridiculous but it worked for him. The pup with the sparkly polish ended up keeping her name.. "Sparkle". I suppose it is possible that the other pups might ingest some polish while playing.