If there are no guts, then you can use parchment or foil.
To do this, cool the blood mixture slightly, and due to the skin emulsion, it will become thick. Put it on parchment and twist it into a “candy”.
If you are not sure about the quality of the parchment, it is better to lubricate it with vegetable oil, and the sausage will “really like it”. I used professional baking paper, it does not require lubrication.