I made this pattern a couple of weeks ago and I thought I'd walk you through my pattern-making process a bit! It's not a full-blown tutorial as I tend to forget to document my progress, but more of an overview.
This YoutTube tutorial by Beret Nice is a very good reference on how to make patterns by hand (minus the whole stitch-it-together-on-your-phone thing which is actually really cool!). It's very close to how I do mine.
Also want to note that my process is a bit tedious and roundabout and you might think why is she doing it this way?! but I've accepted that it's the way I like to work best. If you have any other tips please share!
First I start with a pencil drawing on a square. It's kind of tricky to explain but the YouTube tutorial mentioned above explains/shows this better than I do here. Before I cut it up like in the picture I start with the square (in this case 5x5") and draw all of my elements in the middle of the square. You can make it as big as you like as long as you don't touch the edges.
Then, you have to muster up the courage to cut through the work you've been doing the past hour and slice the drawing into four equal parts. Then you do a little dance with the paper (metaphorically) and switch the left pieces with the right and then the top pieces with the bottom. Carefully flip all of the pieces over and tap them together on the back.
Flip the paper back over and fill in the middle with more art. And now you technically have a repeating pattern square! Go ahead and scan it in.
I bring it into Photoshop and hit Edit -> Definite Pattern. I fill in the pattern in a new document. Now, it's not perfect, but you can see it definitely repeats.
So THEN I take the original square and bring it into Illustrator where I trace and color the elements and add a little texture. I then take those vector images and make a pattern in Illustrator similarly to how this person does it.
Told you my process was a little tedious, but it works for me! Sorry it's so glossed over. Next time, I'll do a much more detailed tutorial on how I make my patterns but I thought it might be good for now to do an overview. :) Happy patterning!