Self check in after 18:00. A door entry code will be sent to you by Airbnb message at 18:00 on the day of your arrival. You must use the code to open the front door.
If you need the door code before your day of arrival for any reason (for example, you will be travelling and won't have internet access) just send me an airbnb message and I can send you the code immediately. However for security the code will not work until 18:00 on the day of your arrival.