Summarize this article in one sentence.
Run a quick search online for “pop-up card templates” to find a template you want to use for your card. There are many different kinds of templates available, so you’ll have plenty of options. Try to find a template that is not too difficult to cut and glue correctly. For the purposes of this tutorial, follow along with the steps using  the birthday cake template linked here (PDF).

Summary:
Print out a pop-up template.