In this day there is no reason to use anything other than low voltage LEDs. If you are doing it yourself, wire them in parallel, and power them with a transformer that is away from the pool. Keep all wires insulated from the water and you are done. If you want total isolation, connect them to the "Clapper".
If you want something more sophisticated, search online for swimming pool lights. That should keep you reading for a few hours. You then still have the option of DIY, or $$$. Good luck.
I believed this is your email add. I will send you simple diagram. but of course layout should be depending on actual shape/design on your pool.
However if you are not qualified electrician to do the actual installation i would recommend contact a qualified one as you were just putting your life into high risk where as worthy than to hire a qualified electrician. (you and your family who will be using the pool).
The following needs to take into account during installation;
1. Stepdown transformer (220v/12volt) or (120v/12v) depending on your available supply, must be located at the pump room.
2. Use proper cable, in some cases light fixture supplied with very short cable you must either change the cable from the unit straight to the transformer and or install water tight junction box by the floor. ensure that the cable looping is enough when you pull the light fixture during the bulb replacement where draining of pool water level is not necessary during bulb replacement.
3. Earth grounding must be connected accordingly.
4. Underwater light fixture must be properly sealed with high performance silicon sealant when fitted.