Note: Notice the yyyy-mm-dd format I use in the "comic for" field below. That's how we're going to tell Drupal to sort the comics (in a later step). Yes, there are other ways to do that, but this way is nice and neat. Also, depending on your theme and the width of your comics, uploading your comics may temporarily "break" your theme. Don't worry about it. If this happens, just take all the blocks out of one of your sidebars for now. Once you have everything else in place you can try out other themes and/or just commit to having either one or no sidebars.
Go to create content >> comic page, fill in whatever you want to name that day's comic.
Hit the "browse" button and navigate to the image you want to upload.

Then hit upload, and you should see a thumbnail of your image, like this:

Type anything you want in the body, or nothing at all. I'm a big fan of transcriptions, personally.
Now scroll down to Scheduling options and click on that field to expand it. If you want the comic to publish immediately, you can skip this step, but this is where you can set a future publication date For example, say you're going on vacation but want regular updates to continue while you're away. This little widget will save the day for you. If you want, you can set a comic to show as though it was published on a past date--This can be handy if you're migrating from another webcomic solution with a backlog of comics. Note that the published on field requires a time as well as a date.

Now, assuming you've been paying attention and have a few more comics to upload, instead of hitting save, hit "Save and create another."

You'll be sent directly back to the create page. If you don't have any more comics to upload, grab some other images for now. You can delete them later, but if you don't have a few comic pages created before you start the next step, you'll have no way to see whether things work. No need to go overboard--I recommend about five to finish getting things set up. Lather, rinse, repeat as needed.
When you look at one of the comic pages you've created, it should look something like this:

Congratulations. You've just uploaded your first few comics, Don't get too comfortable, though. We've got just a couple more steps to go through to make this a webcomic site.
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