I feel like the cat toys you buy in pet shops are made, not to attract cats, but to attract humans. After all, the toys are there to be sold, and it’s the human who has the money, not the cat. So the manufacturers make the toy look like something the human thinks a cat might like, something cute with bright colours and perhaps a cheeky little face or something, and of course cats couldn’t care less about that kind of thing.
The last few cats I’ve either looked after or owned have ranged from an incredibly hyperactive 1 year old (who once got so excited about a sunbird hovering over the water of the lake that he jumped into the lake itself) to a un-neutered male Norwegian forest cat who at about 2 years old was as much like a surly teenager as it’s possible for a cat to be, to a stout and dignified 14 year old lady.
The only thing all three of them have had in common is that they’ve absolutely LOVED the toy I’m about to describe. Even the old lady cat whose expansive belly made it quite hard for her to run around.
Then you need to go for a walk in your local park, and pick up all the feathers you can see (unless they are old and yucky, and a stick (long and straight is better, but it needs to be reasonably strong).
Another good alternative to an “outdoor stick” are the thin bamboo poles you can get in garden centres, or the ones that are used to support orchid flowers. 
Wash your feathers thoroughly in hot soapy water. The cat will probably end up chewing them, so you want them clean. 
Rinse them well so there isn’t any soap left on them. Try to shape them a little bit when you leave them to dry so that they aren’t too ragged. 
Fluffier feathers will look very bedraggled when they’re wet, but don’t worry once they’re dry they will look fine again. 
Choose your largest and nicest feather as your central feather, and another couple of feathers as the secondary side feathers (right side on this picture). Any smaller feathers you’ve found can go in as well, they will add a bit of weight to the toy. 
Arrange the feathers so that the central feather is curved in one direction, and your secondary side feathers are curved to the other direction. 
Put string against your feathers like this, so there’s a loop on one side. 
Grasp your feathers firmly and wrap the elastic band around them. You’ll need to pull it over the stiring, so don’t leave too large a loop. 
Cut your black thread to around 2 meters long, and thread it through the string hoop, then pull it through so that it’s doubled. 
Take the two ends of the string and wind them around the end of your stick a few times. 
Secure them in place with your second elastic band. 
Congratulations! You now have a finished cat toy.
Depending on how much spin you get on the toy you might find the cotton thread gets wound round a bit, so you’ll need to let it dangle somewhere to unwind it periodically. The cats also seem to like chewing the toy and kicking at it, so the rubber band is ideal but don’t be tempted to add anything metal to it to weigh it down or anything.
Once play time is over you’ll need to hide the toy away, don’t leave it anywhere the cats can access it or they might eat it and choke or something.