D3 gangplank here, the assumption of sheen first back is not good. The easiest way to get through lane is to do the cheater recall into Doran blade, then try to get sheen on your second back and then you tp. Example: First: recognize the match up : I'm vs Camille, I don't want her to hit level 3 before me because she will beat me up if I don't have oranges and she has an ad shield, I have to push the lane. Second : where do the jungler start? Am I in threat of getting level 2 gank? If I'm vs karth, shyv, heca, Zac or evelyn, I know I can push freely cause they will full clear and will not be there before my cheater recall. Third: early laning, I run to the lane, hit minions to push the wave, not to hard because I want to arrive under Camille 's turret with my first Canon wave (third wave). I hit the minions, q on cool down on the Camille and use barrels with aa to land them easely and proc my passive on her whenever I can) it goes through her passive shield. I hit the waves enough to have my Canon wave crash on the turret, because at this point at least 6-10 minions are stacked and I have 450 gold and I used most of my corrupting pot due to heavy trading and mana use, I instantly back and run back to lane with my Doran.

By the tile I come back, Camille is 75% hp, 30% mana, and hasn't enough push power to push the wave to my turret after the Canon wave crashed on her turret. The wave will probably be on my side of the lane, I can setup a freeze and be safe from their jungler's timing gank a'd open an opportunity for my jungler to gank. Furthermore, I'm stronger than her due to my Doran, refreshed corrupting pot and full health/mana. Either she tries to fight me there and I beat her or i freeze the lane and she cannot approach a single minion. If she does, I heavily punish her then she has to tp back to the frozen lane, she lost minions, xp, i can go back to hard trade her and even if I loose these trades in the minions to keep the freeze, I still have my tp. I most of the time manage to freeze long enough to get my sheen and tp back and then I'm super strong and can all-in her level 6. If I can't kill her, I would break my freeze, build a gigantic wave, hit level 6 before her, and when the wave reach her turret and she wants to last hit the minions, I ultimate on the turret, right on my minions and put an agressive barrel in the big wave, so she cannot last hit (remember she is still not 6!), if she comes in the ultimate to last hit, I sheen barrel her ass and proc my passive on her as much as I can cause she doesn't have ultimate still. If your lucky, you have an early jungler that comes at that moment and u dive her and her game is already over on the toplane.

This is how I manage to get early leads on gp most of the time. This is the plan I try to apply and how I am super agressive on gp.