1. Select articles you can write intelligently about from either experience or research.
2. Only write about topics that don't have a lot of competition - this is where finding a niche for the subject helps, like error codes on Trane high efficiency furnaces instead of how to maintain your furnace.
3. Write articles that are 700-1400 words long, but don't use fluff or filler to get to that length. If the article is too short, consider combining topics like "error codes for high efficiency furnaces" with sections on Trane, Carrier, Goodman.