The easiest way to obtain a print from a calotype is of course to scan it and then invert it and fiddle with Levels in Photoshop. This is cheap and nasty of course when what you should really be doing is contact printing to make salt prints.
That is easier said than done. It is one thing to make a salt print from a modern film negative as a contact print with fast print-out times. But the thicker paper substrate of a calotype negative means you need to make much longer exposures, often an hour or more. This means that if you are not careful the highlights start to darken and you end up with an awful muddy print. I can do 6 salt prints in a day and it is always disheartening when the highlights mean the print quality is so poor you just throw them away. To mitigate this you expose in open shade away from the sun with or without a paper diffuser. You can also try waxing the calotype. But it isn’t easy. I have made some salt prints I am delighted with - almost all were on Chateau Vellum paper, the same weight I use for calotypes. Recently I have been getting more success with albumen prints.
Future plans are to experiment with Copper Plate Photogravure.