To have your 'first' revelation, you have to accept an offer you get from a guy named
Mack. Meeting mack is basically impossible, because he'll approach you without option to avoid him
before you leave for the airport for your trip to Tokyo near the end of Chapter 4He'll explain to you how he's a photographer and inquire about Revelations, telling you what they are. Then he'll take you to Downtown Ryukyu in an instant, which there you'll see an old woman on a bike (unmissable, this is still in the conversational dialogue).
After some talking, you'll be in control of Kazuma again, and you won't be able to walk away. So simply go into first person mode by clicking in the
Right Analog and look towards the old woman, it'll show you the

prompt in the corner, so go ahead and press your

button. This will trigger a small cutscene in which a Quick Time Event will happen with 3 buttons. After said QTE has happened, you will have another mini-QTE to pick the title of your blog, so pick what you like. I picked the top option.
After this, you'll then be able to view your own blog, which is pretty amusing if you wish to look at it, but when done, just back out of your blog so your automatically trigger a conversation with mack, popping you your trophy.
Sidenote: Revelations will also give you new moves too, so if you want to learn more moves, remember to keep an eye on your email for more revelation offers. To check your emails, press start, then go to the 5th option down "Email". This is where you'll be contacted about upcoming revelations.