Writers get better by practising their writing AND from reading the work of other writers.
You can do the same.
Read finance reports and documents from inside and outside your organisation with a sense of curiosity. If you read something that seems to be very effective, ask yourself how does it differs from what you would write?
- Is the use of language or structure different?
- Or is the layout of the words and figures done in a way that is especially clear?
- Is it the format and content of tables and charts?
- Or perhaps there has been good use made of graphical features like colours and fonts?
Of course, not every finance document is great but you can learn from those, too. Maybe you will notice something in a document that is ineffective and be able to avoid making the same mistake.