I find TILDs (Thirst Induced Lucid Dreams) really relibable, if you can handle being so thirsty.
They give me 100% reliability of becoming lucid, and I do one every now and again.
The only drawback is that they make you sooo thirsty!

Spoiler for Steps of how I do a TILD:

Has anyone else every tried this? I read it in one of the tutorials (can't find link again)