I know that Lubuntu’s philosophy is to be a lightweight distribution. However, I would like it to use even less RAM and improve performance. What are the methods to do that?
Hi lubuntutr! 
Welcome to the forum! 
While I’m not sure about reducing memory usage, perhaps the article here can help you improve overall performance on your system. However, please note that I cannot guarantee these methods will actually work in your case and could possibly have adverse affects! 
Regards…