The video above shows how the rush works.
The basic gist is sending 2-3 drones(either immediately or the ones that turn in the diamonds first) so that they arrive before any wall-in can be made. Use the extraction trick to get out enough workers.
An interesting thing to do is to make sure you have 50 minerals left to make another worker so you have a chance at recovering in case you and your opponent are not quite dead enough. This is not necessary and sightly slows the attack down.
This is generally meant as an Anti-Terran tactic. Protoss players,given they are not walling off a single base), can be attacked by simply using the extractor trick(which will be brought out faster given the 3 drones mining).
The reasoning for choosing drones is their natural regeneration abilities and the general fact that they will win a flat-out battle against other workers.
This holds true as of 2019
Generally, there is advanced micro for workers despite what others say.
Foot in the door
Get inside the base as quickly as possible to prevent wall-ins.
Prevents Proxy Bases
Have all workers selected, right-click a mineral field so they will gather together. Once they are together, quickly press attack so they will 1-shot other workers.
Basically divide and conquer. Generally since most other players will not care about stragglers since it is only "one worker", it is important to note that one less worker is all the difference between winning a battle and not.
Draw, Divide, and Conquer
Most players will attempt to withdraw a couple or even falhhalf of their workers to chase the initial 3 workers. By defeating the initial force separately from.
Always have the first hit when possible.
Since you have more workers from the outside outputting damage, you will win against the ball of workers since the workers inside the ball cannot attack.
You can't mine, why should they? Mineral income can bring out other marines and zealots, which will be more difficult to put down.