Good advice from @larkstar Would emphasize the need to spend time on your covering letter and tailor it to demonstrate your interest in the industry, role, and company - if you can't be arsed doing this I'm not convinced you ever go the extra mile - some jobs you won't need to, in our you do.
Do not address your covering letter "To whom it may concern" or "sir/madam" - so formal and impersonal. If you can't find a name, address it to the team processing the applications. Recruiting Team, HR Team or Recruiting Manager is more current.
Good writing acknowledges the reader's time - make sure you use paragraphs and space in your letter (It should not be squashed into the top of the page). The first line in a paragraph should be the most impactful - often people only read the first line! And remember to discuss how you can help the company (not how amazing you think you are), when you are selling yourself so you should try making it about them and don't overblow here, it's a delicate balance. One candidate did a book review and gave us an extended reading list on his covering letter and offered to give us further advice on how to educate ourselves - he stood out for all the wrong reasons.
Also consider addressing the elephant in the room, for example coming back to work after a long period of absence or if you are changing industries, you need to spend time explaining why, don't bang on about transferable skills - demonstrate your skills.
Don't be afraid to use punctuation like bullet points - your English teacher at school might not have liked them but they are a good way to trim the waffle and get your point across. And do trim the waffle - filling 2 pages with stuff and nonsense doesn't impress anyone, if you haven't got sufficient experience for two pages that ok - stick with one, brevity is an unappreciated virtue. * *
I rarely read hobbies - do whatever you like in your spare time but be careful your hobbies don't look like they will interfere with your job.
Also I feel the hobbies tend to signal class - skiing, traveling, rugby hockey, DoE - I'm not interested in recruiting someone on that basis, so I would rather it didn't sit in my head. And I also don't care if you volunteer, if you do good on you but it won't make me think you are a better person for milking it on your cv!
When I did read the hobbies section The World Challenge shit that some people like to pretend was helping the poor people in Africa - gave me the absolute rage (but I tried to not let that influence my decisions). Clearly, I don't recruit for the caring professions or teaching and they probably love that stuff.😁