In all seriousness, reading opponents depends entirely on understanding MUs, as well as your spacing and character. If you know your matchups, you'll naturally know the options your opponent's characters have where ever they are on the screen, or on wakeup. Using the knowledge of your own character, you can punish and react accordingly.
Example: Smoke telepunches you, and you know he can teleport next to you while you're knocked down, so you tech roll and jump away.
Example #2: You knocked down Scorpion, and you know he might do one of two things: EX teleport or Takedown. If you play as Smoke, you can bait out a takedown by approaching him as he is knocked down, and Smoke Away to whiff punish. Likewise, if he does EX teleport, you'll recover on time to D1 punish.
Example #3: You're midscreen against Sonya. You know Sonya players love to D4, so you properly space yourself to whiff punish any attempted ones.
Example #4: You're fighting against Cage as Smoke, he does his EX forceball shit, and you know he will want to stuff your EX Shake with D3, so you block low and counterpoke.
Example #5: Kung Lao jumps. This retarded character now has three options: jump in punch, dive kick, or teleport. You expect teleport, so you risk it and let go of block to punish.
Case in point, understand your MUs, know your options, and you'll be able to make reads at any given situation. Of course, this also depends on who you are playing; the top players play at a very, very quick pace, so it's hard to make good reads on them. As in life, some people are just "quicker" than others.