There's no such thing as a set sequence. It's entirely up to you and your taste in music. Regardless of the order in which you learn scales (I'll provide an example later), don't just check boxes when you're learning them. The scales must be carefully listened to. What emotions does the music evoke in you? What happens when you isolate certain note combinations that you feel are "out"?
Definitions like this one help me understand what I mean when I use the term "scale." This way, you're not just doing a "up-down" exercise in a straight lined differently.
Anyway, let's get started with the basics.
To begin, I'm going to assume that you enjoy a wide range of "western" music and that, as your career progresses, you'll look to explore jazz and other more experimental genres.
The major key scale is as follows:
The major scale serves as the foundation for a great deal of music, and it's a great place to start when learning about music theory.
The major scale, which is also known as the "Ionian mode," has intervals of one, two, three, four, five, and six.
While playing the C major scale, label each note with a number, so that C is 1, D is 2, E is 3, etc...
Play the C major scale from C to C. Now, if we try the same thing in G Major, G will become 1, A will become 2, B will become 3, etc.
As a result, we have a way to connect the notes to the root of the scale.
To create other scales, we can apply sharps (#) and flats (b) to these intervals, raising the note's pitch by one step/fret/semitone and lowering it by the same amount by applying sharps. Take, for example:
The Scale of the Minor Key:
As you can see, this is based on the formula (1, 2, 3, 4, 5, 6, 7). In other words, the C Minor Scale is composed of the notes C, D, Eb, F, G, 6=Ab, and 7=Bb. When you practice the two scales, pay attention to their flavors, how they make you feel, and how the various intervals affect the scales.
Modes are a source of frequent and unnecessary confusion for users. More concise and doubtless better worded tutorials on modes can be found with a simple google search. However, in order to avoid bombarding you with words and rendering my response largely ineffective, I will briefly break it down...
A scale's "mode" refers to the distance between each scale degree (1, 2, 3, etc.). There are two ways to represent whole steps in C major: W, which is abbreviated to W, and H, which is abbreviated to H, which is abbreviated to H, which is abbreviated to H.
W W H W W W H
This is how C Minor is mapped:
What's the big deal?
See if you can spot any patterns when I repeat this.
Importantly, majorly, majorly, majorly, majorly, majorly, majorly, majorly, majorly, majorly, majorly, majorly......
In the minor details, I mean......
Is it clear to you? Similarly, in the Minor Scale, the chord progression is formed by W W H W W W H. The not relationships are the same in both scales, but the starting points differ.
Laying out C Major and A Minor shows that they start at different points, but they use the same set of notes.
C is a major scale.
C D E F G A B
An Error of Scale
A B C D E F G
Both songs have completely different tones, despite the fact that they share the same notes. Here are the first two modes of the major scale: major and minor.
In order to keep this short, I'll just skim over the next few scales.
The other modes are as follows. The following is the order in which they are most commonly used:
In the Ionian period (Major)
Eucalyptus (Minor)
Dorian
Mixolydian
Lydian
Locrian
Phrygian
The most popular Melodic/Harmonic Minor Modes are next ( which have different W H relationships)
in the key of C minor
A Modified Ratio (Superlocrian)
dominance of the phrygians
b2 Dorian
Elizabeth b6 (Lydian Dominant)
Scales with Equal Areas
Reduced 7
a complete sound
a quarter of the total
half of the total
Scales from Faraway Places
Minority of Hungarian
Magnificent Scale of Mystery
In no way is this an ordered list of the scales I find myself using, it's just an example of how frequently I use each one.
It's crucial not to overlook arpeggios and chords, but that's a discussion for another day....