If you'd like to learn the craft of letterpress, there are a growing number of classes available. I do suggest that you give yourself ample time to learn printing before getting started on your invitations. You'll obviously need to learn how to operate the press, but it also takes a certain amount of practice time before you begin to get the results you'll like.
If you don't have the right amount of time to invest, consider focusing on just one piece, such as place cards or thank you notes. This will relieve some pressure and hopefully make the process a little more fun. Below are some places where you can learn how to print:
Briar Press Classified
Center for Book Arts
Minnesota Center for Book Arts
San Francisco Center for the Book
Virginia Arts of the Book Center
Chicago Center for Book & Paper Arts
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