Gauge is not important for pattern as long as your squares are all same size.
Will not need whole Ball for coloured Circles - recommend 8 different colours for effect.
Main Colour should be a solid colour Black, White or Grey works best.

MC - Black - need 7 Skeins
C1 - Red - Less than 1 Skein
C2 - Orange - Less than 1 Skein
C3 - Yellow - Less than 1 Skein
C4 - Green- - Less than 1 Skein
C5 - Aqua - Less than 1 Skein
C6 - Blue - Less than 1 Skein
C7 - Purple - Less than 1 Skein
C8 - Pink/Magenta - Less than 1 Skein

No border is included in pattern recommend simple double crochet border in you choice of yarn

Any yarn can be used to make this, just make sure you are happy that all the yarn gives same gauge.
Circles should lay flat before squaring off - if not a change in hook size may be needed.