First, you don't have to reinvent the wheel. You can download a
template from http://www.apastyle.info/content/view/13/31/ or a number
of other places you can find by searching Google.

If you want to learn about making templates -- a worthwhile exercise
but more than just a one-day effort -- start at
http://word.mvps.org/FAQs/Customization/CreateATemplatePart1.htm and
http://word.mvps.org/FAQs/Customization/CreateATemplatePart2.htm.
These aren't specifically about APA style, so you'd have to know what
changes to make.

You'd probably also want to learn about macros in order to automate
the common processes such as formatting references -- start at
http://word.mvps.org/FAQs/MacrosVBA/VBABasicsIn15Mins.htm,
http://word.mvps.org/FAQs/MacrosVBA/UsingRecorder.htm, and
http://word.mvps.org/FAQs/MacrosVBA/ModifyRecordedMacro.htm.

--
Regards,
Jay Freedman
Microsoft Word MVP        FAQ: http://word.mvps.org
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