Tanky build explained

Starting

To start off, get a swift shooter and a Halcyon Potion or two.

Early

After a few minutes of jungling, you should be working toward Blazing Salvo, Reflex Block, Void Battery, and Sprint Boots

Mid

By mid game, start working towards Breaking Point, Crucible, Clockwork, Void Battery, and Travel Boots.

Core

Breaking Point
Crucible
Clockwork
Journey Boots

Final Build

Breaking Point
Crucible
Clockwork
Journey Boots
Tornado Trigger
Fountain of Renewal

Quick and EZ explained

Starting

This build starts the same as the tanky one. Get a Swift Shooter and Halcyon Potions

First Time back

By your first time back to your side's shop, or the jungle shop, buy Blazing Salvo and a Minion's Foot. Don't forget to have a Halcyon Potion or two just in case

Mid

Get Tornado Trigger, Blazing Salvo, and Travel Boots. This build focuses more on speed instead of getting Breaking Point first, allowing you to stack up fast.

Core

Tornado Trigger
Breaking Point
Journey Boots
Crucible

Core

Tornado Trigger
Breaking Point
Journey Boots
Crucible
But the last two items I need suggestions first.
I'm thinking something like
Sorrowblade and Aftershock

Some Tips

Until your core build is accomplished, or the Kraken spawns in, try to farm as much as possible
Ganking can be important if your teammate in the lane is having some trouble.
Try to use

Spectral Smite when your stacks are almost at the max.. This will give a you a lot of lifesteal so you don't have to go back to your base often.