Should have written "a printout from the online IGI"

The quickest way of creating an index of bapts and marriages would be by checking a printout - from the online IGI - by parish in date order against the LDS film of that parish, crossing out the entries which don't appear on the register, and correcting those that do appear if they are spelt wrongly or have added information which isn't on the register. [Or do the same thing with a laptop while checking the film.]
Sue