AutoPlaceDown

ms = 2 -- material slot
turtle.select(ms)
while 1<2 do
 if turtle.getFuelLevel() < 10 then
  print "refuelling"
  ms = turtle.getSelectedSlot()
  turtle.select(1)
  turtle.refuel(1)
  turtle.select(ms)
 end
 if turtle.up() then
  if turtle.placeDown() then
   print "placed"
  else
   print "changing slot"
   ms = ms + 1
   turtle.select(ms)
   turtle.placeDown()
  end
 else
  print "job done"
  break
 end
end