A successful business round does not end when the event does — it starts paying off in the follow-up. At the end of the event you can open My Connections to see the contacts with confirmed mutual interest and pick the conversation back up.
It is the most natural channel for a first professional contact. Send a connection request mentioning that you met at Rodada de Negócios — that alone gives context for the approach and increases the acceptance rate.
More direct and informal, it works well when the conversation during the round already pointed to a concrete next step (sending a proposal, booking a call). Ask for the number during the meeting itself if it makes sense.
Ideal for more formal follow-ups or when you need to send material (portfolio, proposal, catalogue). Write a clear subject line and briefly recall what was discussed.
A general good practice
Follow up within 48 hours of the event. After that, the memory of the conversation cools on both sides and the reply rate drops considerably.