Moving from books to implementations So after a good while of digging and practicing, I think I've managed to gain a decent intuition for some of the very core concepts related to linear systems, filter coefficients/parameters, FIR/IIR filters, the DFT/FFT, analyzing spectra and using statistical measures for random signals (stationary,non-stationary). I have a fairly good idea of magnitude and phase, and implementing and analyzing an STFT.

BUT... I struggle quite a lot with implementing something I read in a paper, especially if it's to do with more practical applications that need adaptive filters or estimating filter parameters. I can follow along for most of the math and understand what is being said for the most part, but find myself very easily lost for weeks to no end.

I'm curious if anyone out there has had similar issues, and if there were any solutions that were particularly useful for getting more comfortable with the core concepts. I honestly feel it would help a lot to have some kind of supervisor/TA that I could go to with my questions. Perhaps there are tutoring/mentoring websites out there? StackExchange is honestly really great, but sometimes I either find myself struggling to ask the right question, or not knowing enough to understand the given answers.
In my opinion,

DSP is a tool. It is interesting in of itself but it is most interesting when used to solve real problems. 

Find an application, problem, or community that interests you. 

Take medical imaging as an example. Understanding the slice theorem is necessary but so is knowledge of anatomy and physiology. 

If something like RADAR interests you, knowledge of RF propagation is essential.

Do you like music? You can use DSP to like it more.

Look at other books beyond  signal processing. Think about how you could use DSP in your hobbies. 

Practicing DSP is about balancing function and constraints.