I was having a dream like any other, unfamiliar places, odd scenarios, in-dream thoughts, and I ended up in a room with really psychedelic eastern style music. Later on in the dream I thought back to that music and told myself, "hey, I could probably go lucid using that music." I definitely wasn't aware I was dreaming yet. As soon as that thought occurred I felt that placid numb fleeting feeling I feel when I almost leave from sleep paralysis.
At this point this voice came over my thoughts. I've named him Rufus. He's talked to me before in dreams during the transition to the lucid state. He's me, but he knows more than I do. Like a guide would. He told me this time to sorta find a catalyst, like something that would bring me to the full on lucid state. He told me to find an image. I was searching my memory, pulling images from every recess of my mind. Turning them over and over and over. Rufus kept telling me things like 'no not this one' or 'these are too big' and 'find a smaller one.' So I found an image of a square, a white small square. I brought the image up until it encompassed my whole vision and when it did I just gazed. It was holy. It was my god. I trailed completely numb. I floated off and just experienced some strange scenes like my room but with really comical but horror style variations. Lot's of familiar static white noise here.

I eventually forced myself awake because my heart was palpitating really hard. Fucking common... :/

I've heard of white illuminated squares being used as gateways in lucid dreams. Anyone else ever experience this?