2. Make your own sky writing
If you want to declare your love, there's no better way than doing it in the sky for everyone to see. But if hiring a plane is beyond your budget, do a Photoshop simulation. First, have a friend take your picture in front of a big blue sky. Open it in Photoshop, set the foreground color to white, then create your skywriting brush. Go to Window > Brushes. Dial the hardness down to 0% and size it to a plausible width. Set your spacing to about 70%. Create a new blank layer, then scrawl your message, writing as an airplane might fly. Dial the layer's opacity down until you can see the sky slightly through. Finally, grab the Smudge tool and push the message around until it looks sloppily realistic.