Write a job ad people finish reading
Most ads list what the employer wants. The good ones explain what the person gets.
Lead with the job, not the company
Start with what someone will do and why it is worth doing. Your history can come later.
Say the pay
People skip ads that hide it. A range is fine. Saying "competitive" tells people nothing.
Separate must-haves from nice-to-haves
A long list of requirements puts off people who could do the job well. Keep it to what really matters on day one.
Be honest about the awkward parts
Early starts, weekends, a long drive between sites. Say so. You will get fewer applicants who drop out at interview.