A lot of people find minor scales to be confusing because when most people start learning music, they start with mainly major scales and end up getting a stronger foundation with those and not minors. Also there are several types of minors which sometimes get confused and run together.
But just because they are different, doesn't mean they are harder, we just might have to spend more time with them because we aren't used to them yet.
1. A natural minor is essentially its relative major that has been inverted or moved around.
C Major -> A Minor:
C D E F G A B C -> A B C D E F G A
Eb Major -> C Minor:
Eb F G Ab Bb C D Eb -> C D Eb F G Ab Bb C
2. Now lets compare the natural minor to its parallel major. (In music, parallel means same letter name.)
C Major -> C Minor
C D E F G A B C -> C D Eb F G Ab Bb C
R 2 3 4 5 6 7 R -> R 2 b3 4 5 b6 b7 R
So we see that one way of looking at this is to say that the natural minor scale has a flat 3, 6, and 7.
3. Another way is to count whole steps and half steps. (This is slightly more time consuming but makes more sense to some people.) In this example the lower case (w) and (h) indicate Whole and Half steps between the notes. Notice the italicized notes are the ones that change.
C w D w E h F w G w A w B h C
C w D h Eb w F w G h Ab w Bb w C
So there are 3 different ways of looking at natural minor scales: comparing them to relative majors, comparing them to parallel majors, and counting whole steps and half steps. Now let's check out the other types of minors.
Natural Minor: C D Eb F G Ab Bb C
Melodic Minor: C D Eb F G A B C + C Bb Ab G F Eb D C
Harmonic Minor: C D Eb F G Ab B CMinor Pentatonic: C Eb F G Bb
The melodic minor seems confusing at first but you just have to remember one thing: It's the only minor scale that is different going up than it is coming down.
C D Eb F G A B C
R 2 b3 4 5 6 7 R
C Bb Ab G F Eb D C
R b7 b6 5 4 b3 2 R
On the way up the first half is minor with the flatted 3, but the second half is major with the same as the natural minor. This is called a melodic minor because it is the most common in the traditional 'melodies' that we are used to. It sounds more like music and less like a boring exercise. The more you practice this scale ascending (forwards) and descending (backwards) the more it will make sense to you.
The harmonic minor is in between the other two. It uses the natural minor's flat 3 and 6 but uses the melodic minor's raised 7.
C D Eb F G Ab B C
R w 2 h 3 w 4 w 5 h 6 wh 7 h R
Notice the interval between the 6 and 7 is a step and a half, (hence the wh). This can be tricky at first, so watch out for it. This scale has a more oriental feel that is slightly more dissonant and could be very useful in creating catchy melodies because it is something that is not heard as often and isn't "worn out".
The Minor Pentatonic is a natural minor but without the 2 and 6. It is the easiest minor scale to improvise with because it eliminates the two most dissonant notes in the natural minor. Read more about pentatonics here.