A 2 year stint doubling up as a customer support agent, doing product demos, and writing sales drips taught me this -

Write choppy copy

Subject lines don't have to be boring

Follow-ups are underrated

Understand your needs through a comprehensive onboarding checklist

Immerse myself in your product or service

Think like your ideal customer

Draft copy with several versions and all possible use-cases

Use the RRR (relevance, reward) framework

Test the emails (a lot of times!)

Suggest A/B tests based on different versions

Use insights to improve the next sequence

A 5-part email drip sequence

End-to-end content production

Reporting on metrics

Best sales emails practices to design a framework