Kim, I would suggest that you start simple. With that I mean with a very simple design, that may only use two or three different elements on one copy of your invitation, and maybe two invitations on a page. This way you don't get too overwhelmed by too many things on your page.
Create a simple invitation in whatever application you want to use for the design (e.g. Illustrator), then copy the design to create a second copy and export as a PDF.
Open that PDF in Acrobat and select Tools>Forms>Edit - you want to say "No" to the question that pops up. You will add your form fields manually.
Then select to "Add New Field" and select "Text Field". Now you can draw your field on your invitation. Add the elements that you want in your first copy of your invitation. Make sure that every field has a meaningful name so that the user knows that goes where. You can also specify font type and size on the properties dialog for a field. Now that the first invitation is done, select all the fields that you just added and copy and paste to create a second set. Move that second set over the second copy of your invitation. This is easy to do because the just pasted fields are already selected.
When you now save the file and open it in e.g. Reader you can now modify the text in these fields. Because you copied your fields, they same field on multiple copies of your invitation will automatically get the information entered on the first copy.
Karl Heinz Kremer
PDF Acrobatics Without a Net
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