The diagram bellow shows the position of notes on the fretboard in standard tuning. This illustrates the frets of the guitar with string 1 the High E and string 6 the Low E. Open string tuning is just right of the number and the || symbol indicates the nut of the fretboard. The | symbol represents a fret. I am only showing the whole notes not the flats and sharps.

The interval between whole notes works as follows: A Full step, B Full step, C half step, D Full step, E Full step, F half step. G Full Step, and back to A with a Full Step.

Another way to show this is: A BC D EF G A.

1-E---||-F-|---|-G-|---|-A-|---|-B-|-C-|---|-D-|---|-E-|
2-B---||-C-|---|-D-|---|-E-|-F-|---|-G-|---|-A-|---|-B-|
3-G---||---|-A-|---|-B-|-C-|---|-D-|---|-E-|-F-|---|-G-|
4-D---||---|-E-|-F-|---|-G-|---|-A-|---|-B-|-C-|---|-D-|
5-A---||---|-B-|-C-|---|-D-|---|-E-|-F-|---|-G-|---|-A-|
6-E---||-F-|---|-G-|---|-A-|---|-B-|-C-|---|-D-|---|-E-|

For a sharp note find the whole note and move up a half step. For Example the first A# (sharp) on the Low E would be on the 6th fret. There is no such thing as a B # or E#, nor is the such a thing as a C flat or F flat.

Flat notes are a half step down from a Whole note. Fore example an A flat on the Low E is the 4th fret. By the way thats the same note as G #.

Dont make this harder than it needs to be. Memorize the intervals and youve got it made.