Whenever I go lucid, my dreams always fade and or destroys my lucidity. My recent LD proves that I kept calm and prolonged it by repeatedly telling myself I wouldn’t wake up, but that didn’t help much. So when I tried to get big, I shrink back down and wake up.
Does anyone have the slightest idea? Emotions are out of the question on this.
Once you see the dream to fade away start rubbing your hands together or spinning around on your axis really fast.
Let’s hope I can remember it. ><
From my own practice:
spinning helps really well… but I had a situation where I was spinning and was loosing it anyway, so I made a desperate move and fell on my back, almost jumped and fell, woke up in my bed, was sitting there for a short while looking at the floor - it wasn’t my floor, I remembered everything and knew of possibility to wake up in false awakening, so it didn’t take me long to understand that dream continues… was my 4th ld, looked there on my hands for a first time, was flying for 1st time and waterbreathing… tried everything I wanted… 
there’s a thread people talked about it already, here is the link for the “how to stay lucid”- thread:
Causing a FA can help strengthen your LD… at least that’s (ALWAYS) been the case for me. 
Focus on what you want to do for a few seconds before you actually do it. That also helps for me as well.