Hi all, I've been meaning to write a nice article about this, but don't ever get the time. It works fairly well for me, except for my marital situation
I'll try keep it short so people will actually read all this

First off - this is NOT an entirely new technique. Im just trying to shrink wrap it into an exercise of sorts.
It seems pretty darn good too.

Externally Triggered DILD = a dream induced lucid dream triggered by a real life source (eg. a noise - watch beep - or light in the eyes)
This involves practicing a dreamsign of the trigger (can take some time), and allowing that to spark your lucidity.

Water Triggered?
Simple. Make a dream sign of water. And then leave a tap dripping in the house. I take no responsibility for angry family members

Steps?
So you want a simple guide? Too lazy to experiment yourself? Fine.. here it is :

WADE - Water Triggered DILD Exercise

1) Practice your recall until you can consistently recall at least 2-3 dreams a night. Please read up on dream journals and recall exercises to do this.

2) For one (1) week, make a dreamsign / habit of water. Every time you see water, or even liquids, do a reality check. If you dont know what a reality check is - read the dreamsigns/reality check tutorial
Make sure this is a natural habitual reaction whenever you see water, before moving on to the next step (IMPORTANT... or you *might* wet your bed!)

3) Leave a tap dripping during the night. No - dont concentrate on the sound - just be aware of it. If you cant fall asleep like that, then try a different tap further away.

Hopefully in a short time you should have a whole heap of lucid dreams - all started from water.
You might even have a lucid dream before step 3 if you dream of water on occasion
Or you might even have one simply cos you're practicing reality checks - it increases your general awareness

You get the idea. If it doesnt work - try figure out why. Have you honestly got water working as your dreamsign? Is it instinctive to check if its a dream? etc etc
And if water dripping doesnt work for you, feel free to try using something else as an external trigger.

The nights that I get to do this, I've had great success. Unfortunately if I do this every night it would be tantamount to a divorce

[EDIT]
As a side note - I've had 15 LD's in the last 2 weeks. Many of them sparked with this method