The thing that worked for me as a trigger is to make a habit of doing one of two things, either a, if you wear a watch, make a habit of looking at it often during the day, then you will eventually do it in your dreams and you'll notice the numbers are all off/weird and this may trigger you to realize that you're dreaming and become "aware" which gives you control of your decisions. The other which worked for me as I didn't wear a watch when i used to do this, is to just make it a habit to look at your hand often, then in your dream state your hand's gonna look all weird cause for some reasons dreams have a hard time making them realistic (maybe the same reason AI art sucks at it, dunno).
Lucid dreams are easiest to get into if you take naps, especially if you haven't had your first one happen yet.
I'd recommend just searching for some starter youtube vids as well that can teach you other ways if the above ones don't work, it's quite an experience. I found one just now that seems okay:
Apppreciate it. Thanks.