Here's a guide from last season for Gangplank
https://www.youtube.com/watch?v=ZBD7Sm1E56Y
there are a few things that obviously changed like no more avarice blade and different masteries, but it's still helpful. As far as laning goes you are fairly weak, especially before you get trinity force, a good time to trade though is when you have your passive up, you will need to feel out the enemy top laner a bit to see what they're capable of and what you can get away with. one thing you could try is running a page with health yellows, MR blues, Armor quints, and AD reds, gives you some great base stats to help you through the early game. For items I usually go
x3, and whatever boots make sense to take, gets you 100% crit, 400+ AD, sheen proc, 40-45% CDR, mana return, pretty much everything you need. for summoners it's
pretty much always, though if you're mid you could go for 