Once you have your whitelist ready for signups, you want to enable access to it for your community in the easiest possible way. The easiest way is doubtless /configure-whitelist announce! Simply pass this command the channel in which you want to announce the whitelist (make sure the bot has Send Messages permissions on the target channel) and the bot will post an announcement as well as buttons to easily start the signup process along with it. The announcement includes details on whitelist requirements, open/close times of the whitelist as well as any other pertinent details. You can post as many announcement widgets as you like in multiple channels. If you want to remove the announcement, simply delete the message in the respective Discord channel.
The channel in which you would like to post the announcement and signup widget. The bot will need Send Messages permission on the selected channel.