I’ve read some posts where natural LDers say they dont do RCs but just know they are dreaming. I can relate to this as I’ve had plenty of LDs during my life and “just knew” I was dreaming.
The question is, did you “develop” your ability to know you are dreaming in any specific way, dream journals, looking for dream signs etc. or did you just get better at “knowing” by chance?
I’m intesested in the best way for me to experience more LDs based on the fact that aparently I’m a natural LDer (didnt know I was until I found this forum) 
Currently I’m doing loads of nose pinching RCs, MILD at night and I’ve tried a few WILD attemts. The closest I’ve come to inducing a LD was this morning by MILD repeating “I will RC in my dream” then nose pinching just as I started dreaming and immediately waking up. 
I fall into this category. I have only ever started a LD by simply realising that something wasn’t right and so i must be dreaming. im not sure exactly what triggers it. It all seems very subtle. It seems to just be realising that something simply can’'t be happening so it must be a dream. Normally things are too good to be true, but sometimes i kinda of realise that scenes or time has jumped. I do sometimes try to remind myself of some of the weird reoccuring things that i should spot that are unique to my dreams, but i am not sure if this has actually helped as i dont recall becoming lucid when one of these predictable things has happened in a dream.
Im not sure if that answers you question at all, lol. Sorry.
I can’t say this for sure, but natural LDers are probably very observant, logical people. They probably notice small details in the dream that just trigger them to know it’s not real. I don’t remember ever having LDs naturally in my life. I didn’t have my first LD until I began trying to LD (although LDing came to me pretty fast, and I actually find it quite easy). But I’ve been able to have natural LDs now that I know about LDing. I can have 2 or 3 LDs a month without using any techniques. Once you get the feel of the dream environment, and once you know what you’re looking for, natural LDing may start coming to you.