It's a good thing I'm not the only one who doesn't know where he'll end up.
The truth is, most of us only discover where we are heading when we arrive...
I used a wallpaper I found on the internet, mirrored it (horizontal flip), then used a clone brush for some additional clouds, and 'unflipped' the text. All editing was done in (the very old) Ulead / Corel PhotoImpact X3.
More Calvin & Hobbes can be found on GoComics.
(Click on the image to enlarge.)
Thank you for creating the comic!