Some would argue that your cover letter is more important than your CV. Either way, having a well-crafter cover letter is key when applying for jobs.
Here are some steps you can take:
Length
You want your cover letter to be in the 'Goldilocks zone' which is not too long, not too short. Your cover letter should be between 200 and 400 words.
Greeting
It's great to nail the greeting. Forget about starting with:
To whom it may concern
or
Dear Sir/Madam
Instead, do a bit of research and find out who exactly will be reading your application and address it to them.
First Impression
Don't start off by saying:
Hi, my name is
They know your name because it's on your CV so just dive right into it instead and let them know how excited you are to be applying for an opportunity at their company.
Specific Examples
Stay away from generic cliche sentences. Avoid saying things like:
I am extremely hard working and a real team player.
Instead, try something like:
During my time at Warehouse Company, I worked closely with the Sales team and increased revenue by 30%.
This is both specific and quantified.
Tailored Is Best
Using the same cover letter for every job is a major no. Craft a separate cover letter for every job you apply for.