To add or remove existing contacts to one of your existing lists, or a new list, first look up the email addresses by searching or clicking into the list they’re already on.
Manually select each email address you want to add, then go to Bulk Actions > Add Selected to List:
Then, choose whether you want to add to an existing list or Create a New List:
Manually select each email address you want to add, then go to Bulk Actions > Remove from List. NOTE: This will only display as an option if all the contacts you’ve chosen are already assigned to a list. This also only clears contacts from the list, it DOES NOT delete them. Clearing simply removes them from the list but leaves them in your overall database.