I've been seeing cute photosets on Tumblr and Pinterest lately showing an envelope made out of a heart. They make it look really easy, so of course I tried it out immediately. Turns out perfect heart envelopes are a little trickier than I thought, so I've added some instructions and a template so you guys can make a heart envelope perfectly the first time. :D
The heart envelope template I've attached to the next step makes a heart envelope that's the perfect size for gift cards or small notes, though I bet you could scale it up pretty easy!