Canvas Layout Explanations?

Canvas Layout Explanations?

Where can I find explanations on how to understand the guides shown in canvas when you move things around?

I spend MOST of my time trying to get sections to align properly when the screen size changes.


An explanation of best practices for layout would help. For instance,
  1. How to avoid a gap between sections if the screen is large (Without making it static).
  2. There are multiple red lines in various places, what do they represent besides where it lines up with another section?
  3. i have learned that lining up sections with other objects, if one is static and the other is fluid, doesn't work well. If you add a section behind the object it works better. 
  4. How do you get an object to stick to the right margin AND to the object to the left of it?
  5. When there are overlapping layers it gives an error, but it doesn't ell you where the error is.