The best to start is to send out a least 50 letters by 2nd class post every week to local companies, (you can get their addresses from Yellow Pages) it not very expensive.
You should get at least 1 phone call every month.
Your spelling should be correct, if you type it up on a word document, you can spell check it, before you print off the letter.
If you cannot compose a letter, you can have a copy of one that I use, you just need to add your details to it.