I treated myself to this book after stumbling across it in the Tate Britain gift shop. You can get also get a Cityscapes version too, and Masterpieces, and Iconic Portraits, but I went for the animals.
The dots are clearly marked in a different colour for each group of 100, and number one begins with a star - can you spot it in the picture below?
You definitely need to concentrate, I went wrong a couple of times but I don't think it shows. It's quite hard to see the picture evolve as you're doing it but my son could spot it from across the room, I guess it's a case of not being able to see the wood for the trees, or the cat from the whiskers?
If you'd like to try one of these fab books, they are available from Amazon. (no fee for me ~ just spreading the love!) and probably most good book shops.
Much as I would like to sit and do another, I really can't keep putting off painting the woodwork . . . can I?