Age: This varies from rabbit to rabbit and size of breed as well, but here we are discussing medium/large meat breeds.  As a basic, bucks need to have their testicles dropped.  5-6 months is the average for a buck but they can sometimes breed as early as 8-12 weeks.  First time does should be have their vents checked.  It should not be pale pink, but red to purple and a bit swollen.
This is the lightest I would go for red.
This is very dark purple. Most of my does fall somewhere between.

Does should be 75% of their adult weight.  This could be as early as 4 months, but some people prefer to wait until 6-8 months, as well as some does.  If you present a doe to a buck and she resists and doesn't lift then she may not be quite ready.  It is also good to double check and make sure that the rabbits you are breeding are a buck and a doe, not the same sex.  Sometimes people mis-sex rabbits.  It has happened to everyone at least once.

When: The best times to breed are in the morning or early evening.  But anytime in the day will work.  Remember to account for your schedule when the kits will be born, count 32 days ahead and make sure it works.

How: Always take the doe to the bucks cage.  Does can be territorial and may attack a buck that is put in her cage.  If all goes well the buck should mount the doe and start gyrating.  Then when he is done he will either fall over to the side or backwards.  Sometimes it will look like the buck is actually bucked off.  This is what is called a fall off.  A good breeding has 3-4 fall offs for the round.  Sometimes people will leave a doe with a buck for an extended period of time.  We have done this in the past.  But we had a doe attack a buck and no longer do that.  Luckily our buck was fine but bucks can have their testicles ripped off.  That method also leaves the possibility of unconfirmed falloffs. 

Since Rabbits are induced ovulators; ova are released 10-13 hours following copulation, I usually return the doe for a second visit anywhere between 1 hour, up to 10 hours later for another 2-3 fall offs . Domestic rabbits have no regular estrus cycle.  They may have periods of anestrus and 1-2 day periods of non-receptivity every 4-17 days.

What can go wrong:
  • Sometimes the buck will mount the wrong end.  He should figure it out.  Sometimes the doe will mount the buck.  She is being dominant and might either be unreceptive, done, or needs a more aggressive buck.  
  • If they don't breed make sure they are in good condition and in good health.  
  • If a doe is about to molt she might not breed or might not take.  Molting a new coat takes extra nutrients and she may not have enough to do that and grow a litter.  
  • During the summer, if temperatures get up to 85 and up bucks can temporarily go sterile.  Keep them cool and that should help.  During the winter, due to waning daylight, bucks and does usually need to have artificial lighting of 12-16 hours.  A regular light will work. 
Note that does may get a bit testy after they are bred and it is not uncommon, they should be better in awhile.  Breeding can also help the "bad" attitude of an unbred doe.  Both are due to hormones fluctuating.

I use metal ones for medium breeds, size 18"L x 10"W x 9"H .  They are easier to sanitize between litters than wooden ones.  For warmer weather I put in a bunch of orchard grass (dry) or straw.  For winter I line the metal box with cardboard, then put the straw on top.  You can also use pine shavings, unscented dryer lint or shredded paper on the bottom for extra insulation. 

Put the nest box in at day 28.
  Your doe should start making a nest in the box and may have what is called a "haystache".  This means that she holds the hay in her mouth.  Keep adding hay if the doe eats it or it falls out of the cage.  Some does start digging in the corner a couple of weeks before they are due.  I usually put the nest box in early so they can get to it and settle down.  Does usually kindle (give birth) at 31 or 32 days, but some are early and some as late as 40 days.  Do NOT remove the nest box until day 40 if you think the breeding was a miss.  I have heard plenty of stories about people removing the nest box on day 35 and the doe kindling a day or two later, usually this means the litter dies from exposure, but sometimes it is caught and they make it.

*Note: always clean/sanitize nest boxes before using and in between litters. 

Kits (baby rabbits) are born both blind and fur-less. So your doe should pull fur off her body to line the nest with a day or so before she kindles or to cover the kits once she has them.  Some does don't pull any fur or not enough.  It is always a good idea to save extra fur (clean fur) just in case. 
After your doe kindles you need to check the nest and remove any dead kits or afterbirth.  I give my mama does a treat of milk improving herbs when I remove the nest box to check it.  Do watch out though as some does get protective of their new babies.  If they are used to you taking care of them they shouldn't mind your scent on their kits.  I check the box daily to make sure the kits are all being feed and remove any kits that didn't make it.

Rabbits have super rich milk and usually only nurse their kits 1-2 times a day and for 5-10 minutes.  Often people think their doe is a bad mother because they seem to ignore their kits, when in fact they are taking care of them.   I check the kits to see if they are being fed.  Kits will not usually last more than 3 days from birth without milk.  Fed kits should have a ping pong belly.

After w week kits should be furred and between 10 and 12 days they should be opening their eyes.  Between 2 and 3 weeks they start hoping out of the nest box.  In good weather you can remove the nest box between 2-3 weeks and in cold weather leave it in until 3-4 weeks.  Check the nest to see if it needs to have a freshening of hay.  Every 7 days maximum the nest box should be cleaned out.  Remove any soiled material and try to retain as much clean fur as possible (until they have enough of their own fur and weather depending).

Other notes
I give my does dried raspberry leaves for 1-2 weeks before they are due to kindle.  This helps tone the uterus and helps ease labor.  I have really noticed a difference.  Spotting of blood before and after kindling is normal, as long as it isn't too much and for too long.

Calcium levels drop during kindling, and can cause trouble during labor.  Some people give their does calcium supplement (tums anti-acids) to help as a precaution and others only during difficult labor.  I usually give a doe kale or some other green leaf high is calcium when they are getting close or look like they are in labor.