Pilot reported a runway incursion at IAG due to confusing runway signs in place during airport construction.

Narrative

After contacting Niagara Falls Ground; I was given clearance to taxi to runway 28R via taxiway D; intersection D1. This airport has a lot of construction; with all runways closed except runway 10L-28R. On the surface of intersection D1; I noticed a painted sign for runway 6-24; and then just beyond it; another painted sign for runway 10L-28R. The presence of the surface painted sign for runway 6-24; followed by the sign for runway 10L-28R; caused some confusion. The confusing pavement intersections contributed to my inadvertent crossing of the hold short line for runway 28R; but the aircraft did not enter runway 28R. I immediately recognized the mistake and contacted the Ground Controller to inform them of the situation and to ask if I should taxi back. The Ground Controller responded that it was not necessary to taxi back behind the hold short line and asked how much time I needed to get ready. There were no other aircraft in the vicinity; and the incident did not result in any disruption to airport operations. I take full responsibility for this inadvertent mistake and want to emphasize that it was not a deliberate action. I have reviewed my taxi procedures to prevent a recurrence. As an example of clear understanding; taxiway D3 has surface painted signs for runways 10R-28L and 6-24. They are placed in the order as the runways are actually located. In contrast; intersection D1 has signs in the reversed order as the runways are located; which caused confusion. To further enhance my understanding and adherence to runway safety procedures; I successfully completed an online safety course.