First get a measurement of the room ( this is square footage) you determine this by multiplying legnth x width.
You will also need to measure linear feet for the corner edging This usually comes in 12 foot legths but can be cut
Measure how high you want the ceiling ( standard ceilings are 7 foot 6 inches but could go as low as 7 foot 2 inches) should not be lower as the door opening is 6 foot 8 inches
Install all the corner edging on the wall, make sure it is level and at the same height all the way around the room.
Now install the hooks into the ceiling joists with a hammer.
you will want to place theese hooks @ 2 foot intervals away from the wall and approximately every 4 foot apart
Install all the cross beam tracking level each peice and secure with wire coming from the hooks You will have to cut the wire yourself as it comes in a roll of up to 100 ft
Install all your full pieces of tile and them make your cuts with a straight edge and a knife