Conversational Cantonese is quite different written Cantonese. When Cantonese is written down the way it is spoken, it is considered an informal piece of writing, as spoken Cantonese contains a lot of loanwords from other cultures, particles and words to emphasize the tone of speech that are only for colloquial Cantonese. The formal way of writing could be found in newspapers, magazines, textbooks, books, business letters, public statements, etc. In writing lyrics for children songs, we use a mixture of formal and colloquial Cantonese. Here is more information about written Cantonese.
Apart from the style of writing, there is also the consideration of which writing system to use. The writing system does not affect the structure of the sentences, it is only a way to write the individual characters. There are two systems in writing Chinese characters, Traditional Chinese and Simplified Chinese. Here we use Traditional Chinese characters which preserve the original thoughts and aesthetics of Chinese characters.
