A note can be flattened by the appearance of a flat sign before it.? A flat sign is always written like this.
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To flatten a note, you play the fret position immediately down ( below) the natural note that it affects.???
From the diagram of your fret board in lesson 1 you can see where the flat notes are situated on the fret board.? If you follow the instructions just given,? you will see that D flat is exactly the same as C sharp.? If you check all the notes you will find the same thing.? B flat is exactly the same as A sharp.? These are known as 'Equivalent Sharps and Flats'.? Is this confusing ? ?? Well not really.? You see, it is very unusual for a piece of music to contain both sharps and flats.? It will contain either one or the other but seldom both.? It is all to do with the key that the music is written in and you will learn more about the key signature later. If you ever did find both a sharp and a flat sign in the same bar just treat them the way you have been taught.? Not wanting to sound repetitious but I'll say it again. If a sharp sign appears before a note you play the next fret position up and if a flat sign appears before a note you play the next fret position down.?
Remember that the flat sign, like the sharp sign is always written before the note even though we talk about the note being B flat etc.?
An important rule to remember which traps a lot of newcomers is that the sharp and flat signs change ALL NOTES OF THE SAME NAME in the SAME BAR after the sharp or flat sign appears.? UNLESS A NATURAL SIGN is written in to alter it.?
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In the bar written above, the first note is F.? The second note is A but it has a flat sign in front of it so is played as A flat (Looking at your fret board chart it is the same as G#).? The third note in the bar is also played as A flat even though a flat sign is not written against it.? The reason is , to get back to the rule, a flat or a sharp sign changes? all notes of the same name that follow in the same bar.? Only the insertion of a natural sign can alter it back to a natural note.?
THE NATURAL SIGN.?
The natural sign looks like this:?
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When you find this sign before a note it indicates that the note is no longer a sharp or flat but has reverted to a natural note.?
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In the preceding example the first note is F.? The second note is A flat.? The third note is also A flat.? The fourth note is A natural, (just called A).? This last note in the bar has changed from A flat to A because the natural sign is written before it.?