I have stopped working on BodePlotGui and have developed a similar tool in JavaScript to make it more accessible (https://lpsa.swarthmore.edu/Bode/bodeDraw.html). While MATLAB is extremely powerful, it is also very expensive.
A MATLAB GUI for drawing asymptotic Bode diagrams
The code here is useful for people trying to learn how to draw asymptotic Bode diagrams. The code takes as input a single-input single-output transfer function and generates the asymptotic approximation along with a description of how the approximation was developed.
For help see: http://lpsa.swarthmore.edu/Bode/BodePlotGui.html and http://lpsa.swarthmore.edu/Bode/BodePaper.html
Note: the MATLAB GUI doesn't display well on all devices (some elements of the GUI may not show up). If you have this problem, simply run the MATLAB command "guide" and open the file BodePlotGui.fig. You can edit the size and layout of the GUI for your machine. Save it, and then rerun the BodePlotGui.m file.