The build order:
for 2 player maps
send first overlord directly to the protoss's natural
send a drone on 14 supply to attempt the 16 hatch
attempt 15 hatch
i) If successful, carry on in a normal macro game,
ii) If blocked head to the third and attempt to build a hatch there, if the probe does not follow play a normal macro game, send another drone from the main to the nat to see if the pylon gets canceled, if it does, take the nat and play a normal macro game if you like.
iii) If the pylon is not immediately canceled and the probe is still blocking the third, begin aggression.
At this point you pull 4 drones, skirt the pylon at the nat and send them to the protoss's natural without the protoss seeing while the probe is blocking the third, they will stop the first photon cannon finishing and prevent the probe at the nat from finishing the wall in.
Send 3 more drones about 15 to 20 seconds behind to bolster the 4 original drones for when the protoss pulls his probes to hold.
When the pool finishes you will make 6 lings and double extractor trick to get a queen build and an overlord with your next 100 minerals. As soon as you have extractor tricked the queen out, you can send 4 more drones. I've been sending 3 drones so far but I think you can make it a lot more aggressive if you send a ton more drones since you only need 8-9 drones to non stop produce lings and the game will be resolved long before you hit sustained production.
All you're trying to do is prevent the wall in from going up, at which point you're trying to kill probes first the same as if you had 7 pooled except the pylon for the cannons in the main will be much later and you have 7 drones with your 6 lings to kill off probes, you will kill off a good number of probes and if he's going to hold you pull back just enough to to let your next set of lings arrive and the natural will be forfeit.
It's up to your own judgement when to stop producing lings if you aren't going to outright kill him and start making drones and expand. If you don't outright kill him and he gets his wall up its usually after losing a shit ton of probes holding to get the wall up as long as you didn't fuck up and he got it up before your 6 lings arrived.
I'm finding that it's often pretty obvious because you'll trade lings for a ton of probes in order for the protoss to get his cannons up and even then won't be able to save his natural and his main most of the time. Sometimes even if a cannon in the front does finish you can run some lings up to the main to kill it and move some lings behind the natural out of range of the photon cannon and deny mining while you drone up and prepare for a macro game from far ahead. On top of this when the engagement is over you have an overlord in his base on 2 player maps and almost there in 4 player maps when he will be no where near centuries or stalkers so he can't sneak anything past you.
Please tear this apart, but please don't bother analyzing my play, I know I'm bad, it's the build I'm interested in having critiqued.