This site uses Jyutping as the pronunciation guide for Cantonese. Like Pinyin for Mandarin, it is a romanization system. Jyutping was created in 1993 by the Linguistic Society of Hong Kong (LSHK). It's a useful tool to help improve your pronunciation and learn new characters!
The official guide provides an introduction to Jyutping.
The official site also provides a table of all the sounds in Jyutping.
After learning Jyutping, you can use it as an input method for Chinese, instead of memorizing the shapes of Chinese characters.
Follow this guide for iPhone.
Follow this guide for Android.
Follow this guide for Mac.
Follow this guide for Windows.
ABC Cantonese-English Dictionary is a dictionary published in 2020 that defines and translates many expressions used in Hong Kong.
Pleco is an app for iPhone and Android that lets you look up several dictionaries on your phone. However, you have to activate "Cantonese mode" to see Jyutping.
Hambaanglaang, a word in cantonese that means "all of it", is a website that hosts hundreds of Cantonese readers with Jyutping. Most also have accompanying videos of volunteers reading the texts out loud.
Kozzi.ca is a Canadian bookseller that specializes in Chinese and Hongkongese books. If you prefer paper copies of books, this is the site for you! I recommend Hambaanglaang paper copies as well as The Little Prince in Cantonese .
For more advanced readers, there is a literary magazine in Written Cantonese, 迴響 Resonate. I quite like their articles.
If slang interests you, or you want to read what people write on the Internet, you can join Cantonese social networks: HKGolden and Discuss.
ViuTV uploads many of their TV series online on YouTube.
TVB is a Hong-Kong based television station that broadcasts news, soap operas, etc.
Disney dubs most of its movies in Cantonese. You can select the langauge in the Disney Plus app.
RTHK, the Hong Kong state broadcaster, lets you listen to their programmes online. It also hosts a few podcasts. I recommend d'État de radiodiffusion, vous permet d'écouter Naked Cantonese for those who are learning Cantonese, and 講東講西 for those who are at a more advanced level.
For those who like linguistics, 絮言．狂想 seoijin is a podcast that discusses languages, linguistics, etc. entirely in Cantonese!