Keep under 150 words, open with thesis-specific context (their portfolio or recent deal), state traction in one line, ask for 15 minutes — not 'pick your brain.' Send from your domain with SPF/DKIM; follow up on days 3, 7, and 14.
Subject lines
Reference sector or portfolio company: 'AI infra — similar thesis to [Portfolio Co]' beats 'Intro request' or 'Quick question.'
Cadence
Three to four touches over two weeks. Each follow-up adds new information — metric, customer, or market signal — not 'just bumping this.'