Most of what I have to say has already been said (opening up smaller less busy fields, etc.). However, working your way up on the training server can be difficult as many pilots have minds of their own and tend to spam the frequency and completely disregard ATC instructions… now that I think of it, this also happens on expert, but eh.
My tip would be to start an ATC Tracking Thread such as @BritishAirways001’s thread which I will link here. People can come and fly to the airport you have open and are much more likely to follow your instructions (and should follow your instructions). If you plan on applying for IFATC, it can also help with preparing for your tests as pilots who are IFATC (such as myself) can attend and provide feedback.
If you do create a thread like the one I linked above, make sure to check out this topic…
Also, feel free to private message me or @ me when you open and I’ll try to attend!
Hope this helps!