I'm not sure what kind of dreams you mean... but if was the sleep dreams sometimes I can chose the dream I want; like if I stare into the darkness of my eyeballs long enough, strange movies start to appear and I start to dream... if I don't like the dream ei. zombies then I wake myself up right away and start again. Other times I make up stories as I'm laying in bed... then it turns into dreams... so that's how I dream?
I'm usually very aware I'm in a dream so it makes good stories and art to make ^-^
As for the aspiration dream...
I think it's something different that having a goal. A goal I can work on, but a dream is something that maybe has to do with more with chance or something that doesn't seem as certain?
Sometimes I think we dream of the things we don't have, like when I was younger I would dream I would have a friend, but I was much to scared of everyone to open my mouth.
I used to dream in elementary that I would become an artist, but now it has become a goal because I can work for it. However, being a successful artist is a different story. So until the future, I can only dream that I'll be successful in someway and hope I'm not doomed lol