You can use one of the built-in process charts in Microsoft Excel's SmartArt feature to create a polished flow chart.

It may be useful to sketch out a handwritten version of the process flow before getting started in Word. This way, you'll know how many levels of each part of the process you must add to the chart ...

Microsoft recently made some significant enhancements to its Visio add-in for Excel, enabling users to create Visio diagrams from within Excel. Here's how it works.