Before you make a jigsaw, you need an image which holds a clue in it. If you're lucky, you'll find one on the internet that you can use but most likely you're going to have to create your image.
This one was made by taking images from the internet and putting them together:
This one was made by creating the clue in pigpen cipher first and then embedding it into an image from the internet. Putting all of the cipher in one spot made it a bit easy because you didn't need to finish the jigsaw to get the code so you'd be better to arrange it differently.
Here's an example (and it would be a challenging one for a jigsaw). I found this one in Canva when I looked up 'fantasy'.
Either find the image in Canva or upload the image to Canva.
You can try all sorts of ways to hide codes in an image. You could hide letters, numbers, colours or codes. Here are a couple of examples:
In this image you can see that there is pigpen code hidden in the shelves. The code spells 'bookworm'.
You can make your own pigpen code at websites such as this one.
Screenshot the pigepen code, upload it to Canva and then add it to the image.
In this image the words 'Count the floating pages' have been put on the spines of the books. The answer to the clue is a number which is the number of floating pages in the image.
Find an online jigsaw creator. This example will use Jigsaw Planet. You will need to create an account to use it.
Go to 'Create Puzzle'. Upload your image and then choose how difficult you want to make it. Remember, try not to make it too easy or too hard.
If you copy the share link when your jigsaw is made up, that is how your players will find it when they follow the link.
Click and drag the pieces into the middle of the screen.
Save the link and embed it into your main image.