I've had one lucid dream. I was actually amazing. It is the bizarest thing.
I had looked up about LDs etc. about a month before, but I had stopped trying.
It's so real I thought that it absolutely couldn't be a dream.
I asked my dad what day it was (I didn't want to ask something more blatant because I was embarrassed - no joke that's how much I thought it was real) and he just made a distinct but meaningless sound. Then I thought "Whoa, this is a dream" so I asked my mum what day it was and she said the exact same non-word. Then the adrenaline started pumping.
I remember reading that you shouldn't fly as soon as you realise because the excitement would wake you up. I just thought, screw that - I'm going to fly up the stairs.
I was really weird because I was kind of tentative about it at first so I sort of 'swum' up. On the way down I just sort of floated/soared and that was too much excitement and I woke up.
A good reality check is asking a specific question or trying to read some text. Like go on the forums, if the text is unreadable, then you're dreaming.