Find a small-ish sized envelope and carefully open it up. This is your template.
Recycle a page from a weeded graphic novel. Be sure it is large enough to fit the template. Trace the template on to the sheet and carefully cut out.
Using the template as a guide, fold the sheet into an envelope.
Use a glue stick on the side edges of the bottom flap and let dry.
Cut a peice of paper or card stock to fit the envelope. (Trace around the envelope and then cut it just a bit smaller)
Find a cool cell from a page out of a weeded graphic novel. (It can be from the same one you used for the envelope or not... the choice is yours.)
Glue it on your card.
Use white out on the inside of the speech bubble.
When dry, write in your own message.