Once the fermentation starts it will be intense for several days. A billion bubbles (carbon dioxide) arise in the must and bubble through the air lock. It should be complete in about 1 1/2 week. Then there will be NO bubbles coming up through the airlock. The fermentation stops when the sugar is gone or the alcohol level is high enough to kill the yeast.
Now let the forming mead sit in a safe place at room temperature for a couple weeks. Gradually a tan debris will form on the bottom of the carboy. This is the dead yeast. If you added fruit this will fall to the bottom or float to the top also. Give it some time so a lot of debris reaches the bottom and then it will be time for the first racking.
Racking is the process of siphoning the mead from the sediment at the bottom. This will help clear the mead and prevent an unpleasant taste from the last glass of your bottled mead (the lees).
I strongly suggest you buy the siphon device shown and described in part 1. It works so well –> put the flexible tube end in the bottom of the lower carboy, pull the plunger back on the siphon, position it in the mead above the sediment and gently push the plunger in and the mead flows into the lower carboy. The equipment is cleaned before use.
At this point I return the bottle to a safe place and check it now and again. When the mead has largely become clear-perhaps 6-8 weeks- do a second racking. Some like to do a third racking. There should be no debris on the bottom now so it is OK to pour a little in a wine glass to examine in the light and to taste.
The mead has been aging all this time and can continue to age in the carboy or in the bottle. It’s the brewer’s choice. Bottling it is done the same as racking. Be sure to clean the bottles well before filling to the narrowed neck. Label the mead with the brewing date and contents.
I like to age it for 6 months total as a minimum. We have recently drunk some mead I made in 2011 and in 2005 and it was excellent so apparently it does not spoil with age. I always have served it chilled.