digitalized note taking

No.13764273 ViewReplyOriginalReport
Without stylus and touchscreen, how do you add your own additional notes on a lecture note or write your answers on question-solution pdf files?
Just realized that LaTeX is shit and I won't be able to add it in the blank space beside the main content or fit some equations into the solution box.
Do I just create a new separate pdf file? Apparently ms word can't decode some symbols correctly during conversions from pdf to docx