Help with motion sickness in VR application

Hello. I am creating a VR application that simulates a visual search task. People are required to "walk along" a linear path. The "walking" is simulated, rather than real walking. Meaning that the person is sitting down and only moves forward along the path with the controller. However, when I tested the experiment, it started to make me feel a little sick and I am not prone to motion sickness. I need help figuring out how to minimize this feeling as much as possible. Can you please give me any suggestion that you have? Thank you!!