When I send out an email to a client, I typically start the email from a timeline rather than using the global + button in the upper right hand corner to create a new email.
One of the main reasons I do that is if I’m expecting a reply or something back from the client, I can change the status of the email to "Waiting" or "Waiting for Client" in the information tray. I can then assign the email to myself, give it a to-do date of the day that I want to follow up with them and then also include a due date (if I've set a due date for the client).
This allows me to go into my to-do list and sort my list by status so I can see all the emails where I'm waiting for a client.
What do you do to remember emails??