I'ts a powerful aid to WILD. You can do it alone or combined with any technique you like:

-Sleep for 6 hrs
-Wake up for some minutes
-Write down that you will have a lucid dream, and what you plan to do in it.
-Go back to bed, and lay face up.
-Relax, try to fall deeply asleep again.

And finally... (here comes the new stuff )
-Every minute (aprox) ... SMILE! and while you smile you think, "I'm entering to my dream, I'm aware, I will be lucid"

It's incredible how smiling helps you entering to a more relaxing state, and helps keeping your mind lucid.
Try it! It worked for me