Create 10 tips for designing newsletters that readers actually open and read.

Context: [Marketing, Customer retention, Information delivery]

Goal: [Higher open rates, better reader engagement, clear and appealing content]

For each tip write:
1) a short description
2) concrete implementation advice
3) the positive effect on reading behavior

The tips should:
- be practical and easy to apply
- consider both content and design aspects
- help capture and maintain the recipients' attention