Lay the hardwood flooring at one wall of the room as normal. Lay the planks up to the point of the curve you need to work around, stopping when you don’t have enough space for full planks next to the curve.
Place one of the hardwood planks on a piece of plywood. Trace the plank onto the plywood surface, and then cut the plywood with a circular saw creating a piece of plywood the same size as the plank.
Set the plywood piece on top of one of the last planks you laid by the curve. Slide it forward on the plank until it touches the curve. Using the curve’s bend as your guide, draw an arc on the plywood piece with a piece of chalk matching the curved area of the wall or floor as closely as possible.
Cut the curve out of the plywood piece with a jigsaw, cutting one-quarter inch inside the curve that you drew, leaving some board to work with if the arc is off. Slide the plywood piece back onto the plank in the floor and over to the curve and see how well it fits against the curve. Keep in mind that one-quarter to one-half inch of the floor by the curve should remain uncovered so that the fit doesn’t have to be exact.
Remove the plywood piece from the floor and trim more of the wood away with the jigsaw if the curve in the piece doesn’t work. Continue testing the piece against the curve and trimming as needed until you get a decent fit.
Lay the plywood piece against the bottom of a hardwood flooring plank so that the square edges line up. Trace the curve of the plywood piece onto the hardwood plank and use the jigsaw to cut the curve out of the hardwood. Put the hardwood piece in place on the floor.
Repeat the process used for the first plank next to the curve for all additional planks that must touch the curve. Put each plank into place on the floor as you cut them.