When to break lane depends largely on how the early game went, and the choices made during your first back. If things went as planned then aim to break lanes once you finish the core of the build:



To end laning simply push down the tower or let yours get taken (however taking your opponents tower is preferable).

As I mentioned during the first back depending on your purchases, different builds will have to be followed.

Boots:


The choice of boots you took will not affect the build path a lot, for the most part ignore them.

The main choice made during the first back was between

vs vs

If Wriggle's Lantern or 2-3 Doran's Blades were part of your first back, go straight for Trinity Force then end laning. Phage was part of the back, aim to get a Vampiric Scepter and finish Trinity Force, however this will not be enough to grant you a strong mid game team fight, aim to purchase a tier 0-1 item to supplement your damage, this can be either The Brutalizer if Ninja Tabi was your choice of boot or simply a Pickaxe or B. F. Sword depending on how how much gold you have.

Here we have 3 distinct transitions as to what our next item should be, for the builds where we already have a Trinity Force and no incomplete items, or our incomplete item was Pickaxe go straight for Last Whisper. For the build where we have Trinity Force and The Brutalizer along with the build where we have Trinity Force and B. F. Sword aim to finish the blood thirster, and finally for the standard build get Last Whisper.

END OF LANING ITEMS:

Doran's Blade x3 + Trinity Force
wirggle's lantern + Trinity Force
Pickaxe + Trinity Force + Vampiric Scepter
The Brutalizer + Trinity Force + Vampiric Scepter
B. F. Sword + Trinity Force + Vampiric Scepter
Sheen + Bloodthirster