Instructions
Launch Minecraft and go to "Singleplayer."
Click "Create New World" and set the game mode to either "Creative" or "Survival." Click "More World Options..." and set the Allow Cheats option to "On." Click "Create New World" to start playing.
Type "/time set 13500" (without the quotation marks) after the world loads. Press the "Enter" on your keyboard to set the time period to nighttime.