I meditate in the evening right before going to sleep. I make sure that everything I need to do is completed and do not check email or use electronics afterwards. This puts me in a good frame of mind for a restful sleep. My meditations are typically short: 5-20 minutes depending on how late it is and how tired I am.
I wake up each morning at 5:00, drink a glass of water, open the windows, close them again, turn on the heaters and then I meditate for 12 minutes, before heading to the gym.
I meditate everyday in the morning or at night. I do it for 5-7 minutes depending on how my morning or night is running
Morning is best, before things get busy. The ideal amount of time is 24 minutes, however getting 5 minutes in is better than nothing at all!