How can I make curved gingerbread sheets for a gingerbread house?

Not knowing your recipe too well I’ll assume a gingerbread with a rollable and cuttable texture, like for gingerbread men.

I would use a few empty cans with a slightly smaller diameter than your tower design.

If you cut the can(s) lengthwise in thirds or so, you can drape rectangular strips of dough over them with only some bend, which will put only little gravitational stress on the soft dough during baking. Make sure that the total width of the segments is more than the 360 degrees circle to allow for shrinkage and some extra to cut the edges to fit.

Bake the dough on the molds (with a layer of parchment, ideally) and let the parts cool on the tins as well.

Assemble as you would for the straight walls. A spare can can help keep the parts upright and in shape until the icing “cement” has hardened.

Consider baking your cylinder in or on a mold. (Idea shamelessly stolen from the Great British Baking Show, where this has been done several times.)

To bake in a mold you would need two pieces that would nest inside each other leaving exactly enough room for the uncooked dough. You would need two to keep the cookie from sliding down/off during the early stages of baking before things firm up a bit. Bake completely and cool slightly inside the mold to prevent sagging, then unmold to finish cooling. The benefit of this method is that it allows for a complete cylinder in one piece, but the drawback is having to find two appropriately sized cylindrical pieces of metal or ceramic to bake in (ideally the outside at least is springform, so that you can get the mold off of the baked cookie), which I suspect may be difficult. An easier alternative may be to find something appropriately sized that you can line with cookie dough, and then line and fill the cookie dough with something like rice or beans to bake (think blind baking a pie shell).

Baking on a mold would be much easier. Simply find a couple of half-circle molds, which you could perhaps make yourself with bunched-up foil, drape the dough over and bake. The downside to this method is of course the seam, but it does require baking only two pieces, so only two seams.

Personally, I'd take the blind-bake style approach above, providing you can find a correctly sized cylinder for the outside.

OK, considerable work, but if you cannot get bending while warm of mold ideas that seem promising, you could construct it out of baked or cut circles stacked and mortared together. A lot of circles of course and you may need to reinforce the inside to keep it stable. You could even do it from blocks, but that would be even more tedious construction.

Stella Parks recipe will curve right out of the oven. You have about 45 seconds until it starts hardening. Use ov-gloves or something similar bc the dough is SUPER HOT.