Settings I use to get an IR look in PS

[JonMikal]

After selecting an image, I go to channel mixer and make the following adjustments:

out channel: gray
red: -35
green: +200
blue: -70
constant: +6
check the monochrome box

after you save the image, you can make further adjustments using curves, etc.

hope you find this useful.

 

[Sk8man]

in addition to this, i do this:
1. select the original layer
2. select the green color (Ctrl+2)
3. go to effects>blur>gaussian blur
4. set to 4 and press OK
5. go to edit>gaussian blur
6. set the mode to Screen
7. play with the Opacity bar until you're satisfied (10% for this image) and press OK
8. go to Layers>flatten image

have fun