G28; auto home
G1 Z15 F300; linear move, 15mm vertical and set feedrate at 300
M107; turn fan off
G90 ; absolute positioning
M82 ; This command is used to override G91 and put the E axis into absolute mode independent of the other axes.
G92 E0; set absolute position
M107 ; M107; turn fan off
G0 X10 Y20 F6000 ; move to X 10 mm Y 20 mm , feed rate 6000
G1 Z0.8 ; move Z to 0.8 mm [WHY MOVE VERTICALLY?]
G1 F300 X200 E40 ; push 40 mm of filament while moving at 300 mm/min to position X=200
G1 F1200 Z2 ; move to position Z=2 at 1200 mm/min
G92 E0 ; set the  extruder position as the new zeros