With the image open in PS, choose Image > Image size (or shortcut Shift + Ctrl + I) then set your desired witdth & height in inches, and change your resolution to something higher, like no less than 300 but no more than 600 pixels/inch
Yes you are faking it when you increase the resolution, but for an image that small it will be fine.
Yes you are faking it when you increase the resolution, but for an image that small it will be fine.