You might find it useful to connect to a database and explore your data using QMF Visionary's query tools. Using workbooks and Query wizards, you can retrieve broad result sets of data and discover how you might want to narrow your queries.
For example, you might retrieve all grocery departments to see how many departments there are. You might decide to separate specialty departments such as liquor and gifts from staple departments such as produce and meats: this allows you to tighten the scope of each layout and prevent information crowding.
Or, you might want to retrieve sales revenue totals for all stores and determine the range of totals before you decide what upper and lower limits you want to specify in a bar chart.