DILD simply stands for "Dream Initiated Lucid Dream" and it just means becoming lucid from a normal dream, usually when you notice something strange, doing a reality check like the nose pinch, or through training yourself to stop and really think "how did I get here? Where was I before this?" that sort of thing during your waking hours, the idea being that you'll do this in a dream, discover you don't know how you got there so must be dreaming.

This site has a TON of interesting and useful information, and lots of experienced lucid dreamers which hopefully you'll find interesting and useful!

I also have an issue in my dreams where I can do things like fly and breathe underwater but these don't seem strange to my 'dream brain' and I just continue in the dream as if all is normal and never become lucid. My dreams are often different and interesting, though I wish these strange situations would cue me to become lucid - I'm working on it!