If you don’t know who you should send the cover letter to, do some research into the company and find out who the hiring manager is. Alternatively, find out who the personnel manager is. Showing that you have done some research will be a positive point that the person who could hire you will note.
When you write any cover letter, you should have the job advertisement to hand. It is useful to refer to it so that you cover everything that is required. Use phrases and some words directly from the advertisement or the job description.
Find out exactly what the company does and how it goes about its operations. Ask yourself how you would fit in and how you could help take the company forward. Explain this in your cover (or covering) letter.
In your final paragraph thank the person for spending time reading your cover letter and say that you hope to hear back from them shortly. You could, if you wish, inform them that you will contact them in a week’s time if you don’t receive a reply from them. Although at first sight, this might seem a little too pushy, it shows that you are keen to get the job. It also implies that you have sent other cover letters and job applications, indicating that you are something of a go-getter.
It is important to print your name under your signature, as most signatures are difficult to decipher.