When your beer hits the correct temperature, it is time to move it to the fermenter.  I use a plastic bucket for this, many use a glass container - I have one of these for secondary fermentation on some beers.  The bucket has worked well for me and this one is designed for fermenting so it is much easier to work with than the glass carboy.  My recipe is for 5 gallons (fairly typical) so I poured in my wort and filled to the 5 gallon mark.  

You should have a specific gravity associated with your recipe.  There is a starting gravity and a finishing gravity.  These are usually ranges and you will need a hydrometer to measure them.  The specific gravity basically tells you how much sugar is available for conversion to alcohol.  The higher the starting gravity, the higher the ABV of your finished product in general.  Once your beer is done fermenting, you take a second reading and then there is a simple calculation to tell you what the ABV of your finished product is.  

I should have taken a specific gravity reading before filling it up - mine turned out too low which I hope will not hurt the beer too much.  I could have shorted my water fill a bit to keep me in the range for the recipe.

Once you have all your measurements complete, you cover up the fermenter and add an airlock to allow the fermentation gases to release.  You should start seeing bubbling in 6-24 hours.  Keep the fermenter in a cool dark place and leave it alone.  Fermentation can take 2-3 weeks.  I chose the work out corner of our basement - it will certainly not be disturbed there!

Here is my brew waiting to ferment.  I will check it later today - the airlock should be bubbling which means the magic is starting!