There’s easy ways to bring them on I think although everybody’s different.
I’ve been able to change my sleeping pattern so I go to sleep twice in a day for shorter periods. That makes for _two_ dream times. When I wake up, I take the first few seconds before my eyes open up and quickly start grabbing the ‘gist’ of the stories and a few ‘hooks’ within it and reformulate it a few times until I have a skeleton narrative.
What I mean by hooks is I try to hook aspects of the dream to my last one or two waking periods; I try to think “What could this part of the dream have been related to? Oh yes! It’s that conversation I had about [x] subject where we talked about [y]”… that kind of thing.
What sucks is I only get a few seconds to do this all in… All the thoughts are overlapping, chatting, images intersecting, things zooming and fading away, and it has to become something that could be turned into to something logical and coherent later on like a writer scribbling notes on random index cards and hoping they can put them together into a story later, with one of those cards a loose outline.
This is more what I stumbled on and no idea if it works for anybody else but the one universal seems to be practice helps with whatever you to do remember.
And for the bright vivid? Sometimes eating before bed helps. [it helps some people]. So does being hot while you’re sleeping.