Starcraft 2 - Macro DOES get you Promoted

After struggling for two seasons to improve my league ranking, I've finally finished the season at Rank 2 Gold, and I'm now regularly playing (and beating) Platinum-rank players.

What changed?

Okay, MAYBE I've got better game awareness, and I've been playing more smoothly.  I've stopped making some mistakes, and learned what builds I can get away with.

However... my secret is MACRO.

As Zerg, I've been nailing my injects, and this has allowed me to spend my resources.  I couldn't believe how much of a different this made.  For Terran or Protoss players, that would mean constant SCV / Probe production, and building enough production structures to match income.  I just find that I have more stuff, and never get that moment of "Omg, how does HE have so many troops?".

The second secret to Zerg macro that no one mentions is EXPAND AGGRESSIVELY.  Don't worry so much if you can absolutely defend the expansion - most of the time, when you can afford the minerals to expand, it's time to expand.  This step is similar to Protoss or Terran building more Gateways or Barracks/Factories.  Hatcheries provide more larvae, which allow you to spend resources.  Zerg also needs to aim for AT LEAST 70 DRONES, and since you only want 22 drones per hatch (16 on minerals for minimum saturation and 6 on gas), that means you want at least 3 bases mining by midgame.

Some practice suggestions:
- Play against the Very Easy computer, and try to get maxed on Roaches by the 13-minute mark (EDIT:  in LotV, you can do this by the 7:30-8 minute mark).  Yes, it is possible.  Doing this will give you a sense of what your drone / expansion / queen timing should be when you're powering (for e.g. vs. a FFE Protoss).
- Play against the Very Easy computer and try to get as many Drones out before the 9-minute mark, which is when a Protoss FFE build will start generating any significant number of attack units.
- Play some custom games against your worst matchup.
- Watch your replays.  Focus on one aspect at a time.  It's a lot easier to notice your mistakes when you're not in the game.

But most of all, PLAY THE DAMN LADDER.   Many people are nervous to ladder, but keep this in mind:  if you're losing, you're getting closer to playing people of your skill level, which will be more fun than getting crushed all the time.  Also, you never improve as much as when you're playing against people that are better than you.