Dreamy eyes usually have dilated pupils. I'm sure pupil dilation occurs based on how much lighting there is in the room. Dilation of your pupils is not something you can do on command, it is your bodies natural reaction to the environments change in lighting.
Don't focus on WHAT your eyes look like (that is reliant on lighting, genetics, and eye health). You don'y really have control over this.
Focus on WHERE they are looking. That is what eye contact is.
Basic eye contact rules:
You are listening to someone: hold eye contact 60-80% of the time
You are the one talking: hold eye contact 40-60% of the time
When your not looking at them you are breaking eye contact. Be careful how you break eye contact, if you break it too soon or too often, you will feel submissive to them. That's at least what I noticed happened with me when I was first experimenting with eye contact. I'm assuming they will think you are submissive as well, I mean just think about the guy who is nervous and won't look you in the eye.
Then there is the other side of the spectrum, holding eye contact too long. This can come off as your really engaged, your dominant, or your creepy. It all depends on the context.
How you use your eye contact will always be situational. Someone shifting their gaze often could be uneasy and nervous (low value) or they could appear disinterested and bored (high value) depending on the context.
Breaking eye contact above is dismissive and is a way of saying your above someone
Breaking eye contact below is a sign of submission and you definitely dont want to do this infront of girls
Breaking side is neutral
Try playing around with all of these avenues of experimentation and let me know what you find
Best Wishes,
Lord Byron