A very interesting web with great suggestions: https://www.caeexamtips.com/writing/

If you are looking for practical tips, typical mistakes, useful phrases and synonyms, this is great advice: https://cnmvslobozia.ro/wp-content/uploads/2014/05/CAE-.pdf

You can’t cook without a recipe

A lot of students hate planning and think it’s a waste of valuable exam time. But do chefs walk into a kitchen and just start cooking? Of course not – they lay out their ingredients, make sure their utensils are clean, and have their recipe nearby.

Your plan is the recipe you’ll use to cook up a great piece of writing. Think about how many paragraphs you want then get some ideas about the content of each. But even at this early stage you should start planning the language you want to use. Ask yourself questions like:

  • Where can I use a passive form?
  • Where can I use an inversion?
  • What CAE-level vocabulary do I know about this topic, and where can I use it?
  • How do I link from one paragraph to the next?

Thinking about solutions before you start writing is the easiest way to solve problems!

English linking words

How to write a C1 essay/letter/report/proposal