How to match this wall texture
That's known as a "knockdown" texture, as it's sprayed on the wall and later "knocked down" with a wide taping knife. 

Exactly how it's done is beyond the scope of this answer, but here are some resources.


http://www.familyhandyman.com/drywall/ceiling-texture/how-to-apply-knock-down-texture/view-all
http://homeguides.sfgate.com/install-knockdown-texture-drywall-surface-21287.html