You can document your code using XML comments. Documentation here: https://docs.microsoft.com/en-us/dot...-code-with-xml

So for example, if I have two sub-routines named Sub1 and Sub2, and I wanted anyone looking at the code to know that Sub1 is important to Sub2, then I could do the following:
Code:
''' <summary>
''' here is a description that shows up in the IDE
''' </summary>
''' <see cref="Sub1()"/>
Private Sub Sub2()
    ' blah blah blah
End Sub
Now if I put my cursor over <see cref="Sub1()"/> and hit F12, I will jump to the Sub1 method.