Yori is the basic particle for comparison. Place it after the thing you are comparing against. The sentence then states that the topic is more (adjective/adverb) than that thing. For example, 'Kono hon wa ano hon yori omoshiroi' means 'This book is more interesting than that book.' The adjective or adverb comes at the end and is not marked with 'yori' itself.

You can also use 'yori' alone to mean 'rather than' when choosing between options. For instance, 'ocha yori koohii ga nomitai' means 'I want to drink coffee rather than tea.' In this case, the preferred option is the subject or topic, and the less preferred one carries 'yori'.

Be careful: 'yori' is a particle, not a suffix. It does not change form. It is used in both spoken and written Japanese, but in very casual speech, people might use 'yori' in shortened phrases like 'sore yori' (more than that / rather than that), but that is still standard.