Dig in and experiment with your own systems as well. Virtual machines are your friends just as well as low resource machines like multiple Raspberry Pi's or tiny vms. Then host some websites, and other things together on a single box. Run your tests and watch how the various systems work or do not work, and affect each other along the way. Also to be clear, there's also a big difference between being an expert in HP LoadRunner Analysis software package for looking at test results and doing actual analysis of said tests. I still find it much much more beneficial to do the analysis active and live while performing the actual tests against the sut instead of post analysis. If you are dealing with Java or .Net then the HP Diag probes are essential and offer a great window into the systems live while things are working. Interning even non traditionally will be a great help to you as well! Find someone you trust and know to be an expert already in the field and see if they will spend the time with you to pass on the craft.
