For me, what worked was switching to a new layout (QWERTY -> Colemak) which made looking down entirely useless. Tape a printout of the new layout to the top of your monitor for the first few days until you've got it, no matter how slowly you're typing, then go cold turkey. Some time later I went back to QWERTY in the office and was able to pick up touch-typing that layout without much thought or trouble; now I can jump back and forth between the two. Colemak feels a lot more ergonomic, too, as an added benefit.