Triads
Major scale = 1,3,5 or the first note in the scale, third note in the scale, and fifth note in the scale.

Minor scale = 1, b3, 5 or the first note in the scale, flat the thrid note in the scale and fifth note in the scale.


Here are some shapes of major triads(note where the root note is)
Now slide these up and down the fretboard using the root note to name the chord(triad)
F# chord
D chord
B chord