We've already learned how to play triads with the root on the low E, but that's a limiting way to think about triads.
Let's explore how we can play triads elsewhere.
For now, we'll just look at four triad sets: Major, Minor, Diminished, and Augmented.
However, the same thinking can be applied to sus2, sus4, or anything else you can think of.
Below, I've shown how to play a Major Triad with the root on the E, A, D, and G strings. Notice that the shape remains the same on the A string, but is altered on D and G. Of course, this is due to the B strings relative variance to the bottom 4 strings.
I've marked any altered notes in blue.
Rather than trying to remember three shapes, I find it easier just to think of it as one shape that we can alter as needed.
Here is the minor set.
Once you're comfortable with Major and Minor, you can move on to Diminished and Augmented.
If your head is spinning, come back later to these triads. You don't need to learn everything in one go!
Here is the Diminished set.
And here is the Augmented set.
Keep in mind - you already know these triads. All we're doing here is learning how to manipulate them to work across different string sets. So it's less about memorizing 12 shapes and more about building fluency with how the guitar works.
Once this sort of triad movement becomes natural, we can look at How To Practice With Triads.
Or, jump into some more shapes with Triad Inversions.