Finally figured this out so sharing it here:
Open your image. The image I chose resolution of 72.
Change the resolution to whatever you like. Here I chose 300. Next to "Resample", from the drop down menu choose Preserve Details.
You can also choose Noise Reduction if you like. Here I chose 85.
This is the final product at 100% without "Preserve Details".
This is the final product at 100% with "Preserve Details".
