I teach using the Textbook published by the Chinese University of Hong Kong You can buy a ebook copy on amazon, and …
It is a video by a Cantonese learner from the UK. He introduced a series of books and why he used them.
It was published by Hong Kong Government School for British Officials since 1970s. It is certainly the useful resources for self-learners.
it is colorful
contains a lot of useful phrases
contains funny expressions
easy to find the expressions you need, (it is divided into several categories, like social, meeting people, romance)