Best practices for direct mailing

Hi there,

I am into the business of carpet cleaning. I am looking for promoting my business. I have been getting various ideas, but have to choose the best that will affect my business in the best possible way. So, I am planning to go for Direct mailing, or rather, direct mail marketing. So, I am looking for the best practices for direct mailing, .- http://www.troimail.com/blog/direct-mailing/best-practices-for-direct-mailing/ . Targeting the campaign, personalizing your mail, including multiple ways to respond etc are some of the common ways. Something new other than this ? Any advice would be greatly appreciated!! Thanks .