VistaPrint free kit arrived!

I just received my VistaPrint free wedding sample kit, and, I have to say, the stuff looks really nice!

For those of you who used VP, how was the process of picking everything out and putting it together? For my STDs, I don't think it would be too complicated because it's just one card. For invitations, you have multiple cards...I'm scared I'll get confused/forget to include something.