There is a simpler way to memorise this at the start.
Let's go one by one. Say for Major. If im not wrong its W W S W W W S.
This means it is Whole tone, Whole tone, Semi-tone, Whole tone, Whole tone, Whole tone, Semi-tone.
There are 7 "main" notes in music. A B C D E F G.
B to C is semi tone. E to F is semi tone as well.
Semi tone means there ain't any sharps or flats.
So for example, 1st fret of the 6th string which is the low E, is F. Cause E to F no sharps or flats.
So it will be...
1st - F
2nd - F#(Gb)
3rd - G
4th - G#(Ab)
5th - A
So on so forth. Can get it? Sorry i'm not so strong in my theory but its a way i use to try to figure where the notes are. After you get this "basic idea" right, with constant practising, yeah i guess you will remember it sooner or later.