In my opinion, the best way to learn to play this game is by learning one build versus each race and practicing it until you get decently solid with it. In addition, these builds shouldn’t rely on one brilliant “miracle” attack. Although these timing attacks or allins will get you a lot of free wins at lower levels, you won’t actually improve in the basics of the game such as macro, scouting, and economy management, so eventually you’ll hit a plateau where your attacks are more likely defended than not. With a macro style build, you can learn all the branches of the build and improve on your basic RTS skills. When you begin to learn other builds, your experience and these skills you’ve learned will transfer to those builds as well.
In the protoss help-me forum, every few questions is someone asking for such good, solid builds versus each race. While I’m glad to answer, it gets kinda repetitive posting the same response each time. The following builds/openings are all considered “safe” in that if you play them correctly, you are guaranteed to get you into the mid game. There are no builds from the opposing race which results in a build order win, and these builds allow ample room to deviate and react to your opponents’ builds.
2 gate robo
This is the original “safe” build for PvT. You get an observer fast and respond accordingly to what your opponent is doing. Its weaknesses include lack of early pressure and a slightly weaker economy that some other builds may provide. This is the quintessential good starting build to learn with, as you don’t have to make as many reads based on experience with the essentially free maphack the observer gives you.
1 gate fe
This is a slightly more advanced build that can give you a better economy leading up to the midgame. The biggest problem for this build is that you need to make some early game reads to properly respond to certain openings from your opponent. Because of this, I recommend you learn it after you master the 2 gate robo build.
3 gate expand
This build is the first “standard” build of PvZ. It works on every map, and gets a healthy amount of units before expanding. After your expansion gets up safely, you have a wide variety of options open to you. These include but are not limited to hallucination scouting, 3-5 gate pushes, stargate pressure, fast robotics, or blink.
2 gate stargate
This build is not recommended much, because it’s not as “standard” as a 3 gate expand, but I would say it’s the 2nd most popular build that’s not forge fe. And according to oGsMC, it is the safest PvZ opener, and I agree with him. This build lets you get up an expansion even more safely than a 3 gate expand, as it shuts down any 2 base roach ling allins more easily. In addition, you get early game map control and can apply a little pressure.
Forge fast expand
Although this build is not viable on all maps, it is actually the best opening possible on a majority of maps. I do not recommend this as a first build for players, as the order of buildings is different for every map and versus every zerg opening you scout, so it can be confusing for newer players. However, I do recommend every single protoss player eventually learn this opening, as it is a necessity to not fall behind on certain maps.
2 Gate 3 Stalker Rush
Besides proxy gates and cannon rushes, pretty much the only early game threat in PvP is the 4 gate. Thus, all openings anyone can recommend will revolve around defending a 4 gate. This particular opening is very standard and doesn't require the level of execution as say a 1 gate defense would. Once you are comfortable with PvP and this opening, you can move onto other anti 4-gate builds such as those outlined here in the compilation of anti 4-gate builds guide.
Note: Changed my PvP recommendation from Geiko's 3 gate to 3 stalker rush