The window matters more than the wording. After a week the conversation has faded and your message requires them to reconstruct who you were. Within two days it lands as a continuation of something already begun, which is an entirely different reception.

Reference the specific thing. Not the event, which they attended alongside forty other conversations, but the actual subject you covered. That single detail is what distinguishes a genuine follow up from a mass message sent to everybody whose card was collected.

Deliver what you promised, and if you promised nothing, send something small anyway. An article relevant to what they described, an introduction to somebody useful, or an answer to a question they raised. The act of giving something first establishes the relationship on the right footing.

Keep it short and put no pressure in it. Three or four sentences. Somebody you met once owes you nothing, and a follow up that immediately proposes a meeting reads as though the conversation was a qualification exercise rather than a conversation.

Make the next step optional rather than requested. Saying you are around if it comes up leaves the door open without asking them to walk through it. People respond to that considerably more often than to a proposed time.

Connect on whichever professional network they actually use, with a note referencing the conversation rather than the default request. A bare connection request from a name they half remember is usually ignored, and one carrying a sentence is usually accepted.

Record what you learned somewhere durable, because you will not remember in three months. What they do, who they serve, what they said was difficult, and anything personal they mentioned. That record is what makes the next contact possible and the relationship real rather than transactional.

Then contact them again in a few months with something useful rather than a request. A relationship maintained at low intensity over a year produces referrals. One that consists of a follow up and then silence produces nothing, and the initial conversation is wasted.

Accept that most will lead nowhere, which is normal and not evidence the approach fails. Three conversations from an evening producing one lasting relationship is a good outcome, and that relationship may generate work for years.

Write the follow up the same evening and send it the next morning, because the detail you need is still available and it will not be in two days.

Send it even where you concluded there was no overlap, since people move, change roles, and know other people. A short courteous message costs two minutes and keeps a door open.

Do not attach anything to a first follow up. A link is fine and an attachment from a name somebody half remembers frequently goes unopened or straight to spam.

Add them to whatever record you keep of contacts, with the date and context, so that a message in three months has something to reference.

Resist proposing a meeting in the first follow up unless they asked for one. The message exists to keep the relationship alive rather than to convert it immediately.

Keep the subject line specific to the conversation rather than naming the event alone, since a recipient scanning an inbox recognises the topic faster than the venue.

Send it yourself rather than automating it, since the whole value is that somebody took two minutes to write something particular.