Do you want to make a network card for your Arduino project?
How about consider a market-proven PCB like a below link? You can easily get a bare-PCB of customized netcard board from OSH Park site.
From the GitHub repo(https://github.com/Sd4Projects/MiniMega2560_NetCard), you can see the schematic, BOM and mounted product as below.
- This board based on vendor white paper http://wizwiki.net/wiki/doku.php?id=products:w5500:refschematic
For more details, please visit GitHub repo or OSH Park link.