To add a server icon, log into Multicraft, select and stop your Minecraft server, then follow these steps:

Icon Specifications:
Size: 64x64 pixels
Filetype: .PNG

Making the Icon:

1. You will need to have a picture or have created a Minecraft server icon.
2. You can convert a picture for icon use using this handy tool: http://www.genfavicon.com/
3. Once your picture is converted. Click the "Download: png" to download and save it to you computer.

Upload the Icon:

1. On your Multicraft panel choose the "Files" menu.
2. Click on "FTP File Access".
3. Drag and drop the your image to your server's FTP File Access. 
4. Click the checkbox next to your uploaded image.
5. Click "Rename" at the top.
6. Rename the image to "server-icon.png".
7. Click "Save" and restart your Minecraft server.