As pointed out the pin layout is the same as a standard 14 pin IC.
To find the bottom of the LED, hold the LED at different angles while viewing the front of the LED, the decimal points will be just visible, they are at the bottom of the LED.
EDIT:
If you are unable to see the DP, use a 330R with a 5V power supply.
By connected one pin to 0V and any other pin to +5V via the 330R, one segment should light, if not reverse the 0V and resistor pins.
Work your way thru the pins, in a few minutes is easy to work out which pin is which.