Poppy top lanes by farming. She scales really well with items, so you just want as much money as possible. If the other person gets gold then so be it. You're more likely to swing a game than they are. Poppy is good against anybody with minimal sustain, and people who can't get past her passive. You also don't want her against anything ranged because she pretty much can't win that. I'd probably take her against people like Irelia or Wukong. Granted, you can easily play her against most tops, but anybody you can free farm against is beneficial. As far as laning goes, don't be too aggressive unless you can get off a stun. Don't go too far out of your way to Q them but Q can be a great denying tool. Skill order (at least for me) would be EQWQQR maxing blow, tackle, then paragon (or whatever it's name is).
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~Acting on Impulse~
Black Turtle still didn't MAJORA'S MASK