No one love spell is "most" effective - in fact, many are faulty. Before you actually look into performing a love spell, you need to ask yourself some questions.
Is this something the both of us would like?
Am I being selfish?
Do I really need a spell, or am I using magick as a quick fix?
Love spells that deal in changing someone's mind so that they fall in love with you do not work. It is impossible to take control of someone's biochemical neuron processes in the way that would be needed for them to fall in love with you. Even if you still want to go through with this spell, check out the different ones on this site. There are many that incorporate candles.