Backup and archive all media.
We can talk about backing up/exporting your blog posts, (like we already have.) However, you should keep all the image/audio/video files you upload to your blog as well. This is because when you migrate your blog to a different service, references to these files will be broken. If you have the files, you should be able to reupload them. If you don’t, well then you’ll never be able to fix the broken references. It doesn’t matter how you backup these files, for me, I have them on my computer, I also have them on an external hard drive. Not only that, I use Backblaze, an online backup service. I’ve learned the lesson of bad backup stratigies, it’s a long story, and I don’t particularly want to tell it here. If you read my posts on Viddler, then you’ll probably understand.