How do you write a character reference letter for a security guard job?

To Whom It Concerns,

I confirm that I have known John Dillon for the past fifteen years. I have always found John to be a loyal, trustworthy and reliable friend, generous in nature and extremely competent, hard-working and consienctous in anything he sets out to do.

John is always willing to lend a hand if you should need assistance and punctual when meeting up.

I am happy to provide further information if required.

Yours Faithfully