How to become a systems developer without a degreeWatch
1) Learn Linux, especially the commands.
2) Gain knowledge of VIM.
3) Knowledge of GIT commands.
4) Know how to deploy web servers/software.
5) Knowledge of how to compile a file.
6) Know how to set up a virtual machine.
7) Know how to configure an infrastructure: such as cloud storage, log errors, monitor systems.
8) Knowledge of Agile principles.
9) Knowledge of the software development lifecycle.
10) Knowledge of wither Java, C# or C++.
You could learn all of this from Google.
Any commercial experience will also help, of course.