What I have found the helps most is to, yes...write them down as soon as possible. When you write them, write it in as much possible detail as you can. Cover the 5 senses & more if you can.
It will take a lot of dedication, but like you guys have noticed, it works & the more you do it, the better it works.
I have a dream journal still from when I was a teenager & did this. I have always had very vivid dreams. I've flown since I was 3-4, and have traveled to many many different worlds. In many different dimensions.
I would lucid dream, bc of my "stalker " to get away from him. He terrified me lol. I was just become lucid & fly away..later/sometimes, teleporting instead bc it's easier (same concept as flying kiiiiinda) well. I can either take my time getting above the tree line & sky line..or I can just put myself there.
So, as I got older (teen years) 15-16.. I wanted to lucid dream more & better to explore more places. I cannot remember how I learned to writeit all out like I did.. I'd even draw pictures lol. I still remember very clearly many of those dreams as well.