This quick ebook will help move from basic usage of Jackson to leveraging the library fully and with precision:
Fully and flexibly deal with POJO properties: Jackson has a lot of options and powerful features - specifically targeted at dealing with standard properties of POJOs. I did a deep-dive into these scenarios here.
Know the Annotations: knowing that an annotation exists - that's a great first step. Knowing when to use it - that's where things get interesting with Jackson.
Go really Custom: annotations are certainly powerful, and you can do a lot. But, sometimes that's just not enough - and writing custom marshalling/unmarshalling code is the only viable way to go.