It really depends on what you're doing. The main thing is to ensure your quotes are relevant and you aren't just quoting them cause you memorised them. If you're naming a technique or idea that is a major point in your essay, a quote is always handy, Apart from saying that, I can give you an example but I'm not sure exactly what you're looking for.
The use of lights to represent both the cyclical nature of journeys and Lewis’ progress was a particularly effective technique in assisting my understanding of the concept of journeys. The contrast of Lewis saying “Where are the lights?” and “Time to turn out the lights,” highlights the control he has gained over his life and ideologies.