Server Icons are a great way to personalize your servers to stand out amongst the rest, or just add some funny picture for your friends to see upon joining the server. This guide will go over the basics of creating such an icon!
Requirements
For a Server Icon to work, it must be the following:
- It must have a 64x64 Dimension
- It must be a .PNG file
- It must be named 'server-icon' (no 's)
These are REQUIRED. If even one of these aren't met, your icon will not appear on your server!
Creating an Icon From Scratch
For those of you that are much more creative than I am, you can create an icon from scratch using any artistic program. From free options such as Krita or GIMP to paid ones such as Aseprite or Photoshop, as long as it can output a PNG file at 64x64, you should be all set! For this tutorial, I'll be using Aseprite.
Whichever program you use, be sure to set the canvas size to 64x64

Then using your artistic talents (of which every one of you likely have more than I), sketch out whatever you wish. Your mind's the limit!
Once you've gotten it done, be sure to export the file in the same size. Most programs will let you rename the file as you export. In the end, I was able to get mine done and exported as shown below:


You'll see that, of course, it currently meets all three criteria, which means it's ready to go!
Using an Existing Image
Don't want to go through making an icon from scratch? That's fine too! Remember, any image works, so long as the requirements are met. But most images don't come in 64x64 format dimensions.
To fix this, we can resize images using either an online tool such as ImageResizer or editing software like Krita. In our case, I'll use the latter.
After opening your desired file in Krita, you can use the shortcut Control + Shift + I to resize the picture to whatever size you desire. Be sure to turn off Contrain Proportions (or a similar option if you're using something else) so that you can get the correct dimensions. For the best quality retention, I recommend using the Mitchel filter (but feel free to play around with it):

Note: You WILL lose quality regardless of what settings you use due to the reduction of pixels. This is normal, but something to keep in mind when compressing images, as shown below:

Once you've gotten it resized, you may now export it as a PNG and rename it as necessary!

Further Reading: Adding the Icon to the Server
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