In a strand of dubbing the fibres should be mixed, they shouldn’t sit side by side, and they shouldn’t really be ram-rod straight. Cut a tuft of hair from a skin and the fibres all lie in one direction, pull fibres from a packet or box and the fibres tend to be aligned, neither makes for easy dubbing. So, to prepare a pinch of dubbing, crumple the fibres and roll them into a tight pill in your palm, then gently pull and tease the fibres in the ball into an open web before twisting it onto thread.
Oliver Edwards was the first to show me this simple technique, it can make dubbing from some surprising materials, e.g. feather barbs and deer hair, and it works with a great many synthetic material, too.