Section A - download blog - you need to do this before Posterous closes on 30 April 2013
1. Log into Posterous.com and click on the 'Backup' button (it should be visible from all pages but if not click on Spaces).
2. Click on 'request back up' next to name of blog, wait a bit, come back later (you'll get an email when it's done) and...
3. Click on 'download' to get a zipped file containing your entire blog, unzip as and when needed.
- Disable the autopost to Twitter and then...
(Spaces > Your blog ('space') > Autopost setup (in panel on right) > hover over Twitter name then press red X to delete)
- ...add a final post saying that your blog is closing / moving (if you do this once you've moved the blog to its new home you can include the new adress).
This means that all your Posterous followers will get a notification but it won't go to your Twitter followers (who don't need this info since your new blog will seamlessly start autoposting to your Twitter account).
Section B - import blog to another host, example given is WordPress.com (free version) - you can do this at your leisure
If you want to move it to Tumblr then Posterous has suggested using http://justmigrate.com/ (you might need to do this before Posterous shuts though) - if you already have a Tumblr blog and it posts to Twitter you'll need to switch off the autopost function before you start the migration.
4. Unzip the zip and note that one of the files is an xml with the word 'wordpress' in it
5. Create a free blog at http://wordpress.com
6. In the dashboard [https://YOURBLOGNAME.wordpress.com/wp-admin/] go to Tools > Import > Posterous and select ('navigate to') the xml file
7. Wait patiently - or just open your new blog in another tab / window https://YOURBLOGNAME.wordpress.com/ - I've moved large blogs and it's been done and dusted within about 3-15 mins but usually takes an hour or so for you to get an email letting you know it's all done.
5b. If you prefer to go for the self-hosted Wordpress.org type of blog then there's a plug in that will help you transfer it (you need to do this before Posterous shuts though http://wpmu.org/posterous-shutting-down-how-to-move-your-posterous-site-to-wordpress/)
To create a new post on your new blog you can just click on 'New post' which appears on most pages including the dashboard, however this brings up a light version which I don't like one bit, I prefer to go to Dashboard, then hover over my name (top right) until the list of my blogs appear (I have several), then hover over the one I want to post to and choose the New post option that shows up there.
I've moved about 8 blogs so yell if you get stuck :)
Section C - customising it a bit
You need to be in your dashboard for this, it's https://YOURBLOGNAME.wordpress.com/wp-admin
- Autopost to Twitter etc: Settings > Sharing > Add Twitter account (also Facebook, LinkedIn, Tumblr)
- Getting rid of the weird tagline they keep adding: Appearance > Customise > hover over panel on right, choose Site Title and then amend text in Tagline field
- Tweak the look / themes / skin: Appearance > Themes
Section D - troubleshooting
The import info says that it will let you "Import posts, comments, images, video, and categories from a Posterous export file" - attached files seem to show up as an absolute link, pointing to files.posterous (though some point to files.wordpress or something like that).
I'd not be surprised if file links might break once Posterous disappears, however you have all the atttachments in the various folders of your zip and can navigate to them and manually upload if necessary. I've got over 800 to do for ScicommJobs so not overly enthusiastic about that ;)