We've covered a lot of ground in this chapter:
How and when to use nesting
How we can use nesting with the parent selector to work more easily with Modernizr
How the
@extenddirective worksWhat placeholder selectors are and how to use them
How to use and write mixins to easily produce code on demand
As such, in this chapter we haven't made much of a dent in the design of http://sassandcompass.com.
However, the skills we've learnt are so useful in everything we're going to write in future; I think that's a fair trade-off.
It might take some time before you find yourself using these features day-to-day. Don't feel like you need to use them right away and at every available opportunity. If all you do for starters is nest and extend the odd style that's still progress, and it will make authoring style sheets easier than before. Once comfortable with that, when feeling feisty in the months to come (and if Compass doesn't already have a feature to solve the problem), maybe take a shot at writing...