solder the 4 LEDs in parallel and all in series with a resistor.
since you dont have the ohm about the LED... im not sure wut size resistor you should use...
as long as you can get a resistor to limit the voltage to around 3.6V, you will be fine. and all 4 LED will receive around 3.6V since they are in parallel.
PM me if you got the ohm of the LEDs.