Putting an outline around an image is a great way to make it stand out and draw attention to it. Here are some steps to do it:
Open the image in a photo-editing program. Popular options include Adobe Photoshop, Pixlr, GIMP, and Paint.net.
Click the "Select" tool and carefully outline the edges of the image.
Click the "Stroke" option on the toolbar — this should open a dialog box.
Adjust the fill and width of the outline to your preferences. Make sure to select the same color as the image itself.
Click "OK" to apply the changes.
That's it! You have successfully added an outline around the image.
Feel free to experiment with the look of the outline. Different colors, patterns, and widths can add to the aesthetic of the image and make it even more eye-catching.
Good luck!