Dealing with data management and precision

As a person who likes to plan and look at things in the bigger picture, I have found managing data to be quite hard work. Especially when the data comes in various forms and in volume.
However, I have found that one needs to be patient and focussed to make sure you can be precise and correct. To check the data one by one; to revisit the same data; to make sure that the data remains same between what you receive and what you key in; all of these are a new set of skills that I am trying to build...