Now that you know how to calculate the number of accidentals in each key, the next step is to learn which notes are sharp of flat).
There's a concept called the “order of flats” and it's inversion, the “order of sharps”, there are the specific sequence of flats and sharps the occur in the keys (the right hemisphere uses sharps and the left uses flats).
To calculate the order of flats, simply start at 5 o'clock and proceed counter-clockwise through 11 o'clock = B – E -A – D – G – C – F and conversely and conveniently, the order of sharps is the reverse of the order of flats: 11 o'clock proceeding clockwise through 5 o'clock = F – C -G -D -A -E – B.
Thus far, we've only be discussing major keys, there are also 12 minor keys encapsulated in the circle of fifths (these minor keys are relative to the major keys) To calculate them begin with Am at 12 o'clock and proceed clockwise in 5ths =Am – Em – Bm – F#m – C#m – G#m. Then proceed counter-clockwise in 4ths = Am – Dm – Gm – Cm – Fm – Bflatm – Eflatm.