How to write a cover letter
In order to write the perfect cover letter, their are two things to consider. Professionalism- no-one wants to read a slap dash piece of work,- and passion, why would anyone hire you if they do not think you are committed to the cause you are applying for?
Remember, your cover letter is not your CV. Your professional achievements have already been stated and possibly being considered. It is now time to tell the reader exactly what you will bring o the table for this specific job.
When writing a cover letter in order to work backstage for a Bon Jovi concert, I stated that like all the other applicants I was a massive Bon Jovi fan, and had been listening to them for years- passion for the band- I then when on to state about the theater shows I had been involved in, and how that had led to me knowing how to be a good runner of equipment and how I had learned to handle members of the audience in a professional way public. Doing this let the reader know not only could I not be pigeon holed, I did not expect to be pigeon holed. Unless the job you are going for is specific, let employers know that you are more than happy to take a specific role, this shows professionalism AND passion, two birds one stone.
Obviously there is a question of grammar and how to address people, if you do not know who you are writing to specifically 'To whom it may concern' can never steer you wrong. It shows the reader that even thought you may not know who is actually making the decision to hire you (and therefore most likely reading the letter) you are still polite, and you don't assume anything. No assumption, no cause for judgment.
Personally I always end my cover letters with either 'Thank you for reading' or 'I hope you will consider me.' The latter may come across as too much in certain situations, as of course you hope they will consider you as you wouldn't have written the letter otherwise, never the less it shows an inch more passion than you have already shown.
Part of the cover letter is you showing why you are better than anyone else applying, and you can use examples of when you bested someone in a work place, but you HAVE to be very careful how you phrase it.
For example, if I was using the Bon Jovi experience in another cover letter I may state 'I was asked to deal with irate customers in order to explain the opening times of the venue, when they were confused that they were not allowed in at the time they arrived.'
I have not said that my other colleagues weren't up to the job, I have merely described there was no-one else for the job at that specific time.
But in a similar vein, don't always isolate your colleagues, you want people know you were a good team player so I may state 'Me and a colleague were directed to decorate the VIP room and serve VIP guests, in order to make sure they were having an enjoyable experience.'
Either mention your colleagues to show that you have worked well with people, or don't mention them at all, adapt it to the situation, you don't want the company to hire them instead of you!
So long story short, professionalism at all times. Passion for what you do and what you want to be doing as relates to the job, and if you have to mention colleagues, mention them in a suitable light.
I hope these tips help you get that next job!