Friends:

How does one gain the Mind Reading Ability?

Once when the Venerable Anuruddha was dwelling at Savatthi in
Jeta's Grove, in Anāthapindika's Park, a number of Bhikkhus went
to the Venerable Anuruddha & exchanged polite greetings with him.
Then they sat down & asked the Ven. Anuruddha: Venerable Sir: 
What has the Venerable Anuruddha developed & cultivated so that
he has attained to his famous greatness of direct knowledge?
It is, friends, because I have developed and cultivated these four
Foundations of Awareness that I have won great direct knowledge.
What four? Here, friends, I dwell constantly contemplating upon:
The Body only as a formed group, neither as I, me, mine, nor a self...
The Feelings only as passing responses, neither as I, mine, nor self...
The Mind only as temporary mentalities, neither as I, nor any self...
All Phenomena only as constructed mental states not as existents...
while eager, clearly comprehending, & fully aware, thereby removing
all desire & frustration rooted in this world! It is, friends, because
I have developed & cultivated these Four Foundations of Awareness
that I have become empowered with suprahuman forces: I directly
understand other beings minds when having encompassed them with
my own mind. I understand a mind with greed as a mind with greed;
a mind without greed as a mind without greed; a mind with hate as a
mind with hate; a mind without hate as a mind without hate; a mind
with ignorance as a mind with ignorance; a mind without ignorance
as a mind beyond ignorance; a contracted & lazy mind as a lazy and
contracted mind & a distracted mind as an agitated and distracted
mind; an exalted mind as exalted into jhāna and an unexalted mind
as unexalted; a surpassable mind as a surpassable mind & a verily
unsurpassable mind as an unsurpassable mind; a concentrated mind
as concentrated and an unconcentrated mind as so unconcentrated;
an unreleased mind as unreleased & a released mind as all released...

Source (edited extract):
The Grouped Sayings of the Buddha. Samyutta Nikāya. [V:304]
section 52: Anuruddha. Thread 14: The Encompassing mind!

More on the Mind:
http://What-Buddha-Said.net/drops/II/In_Control.htm
http://What-Buddha-Said.net/drops/II/Non-Control.htm
http://What-Buddha-Said.net/drops/II/Blazing_&_Bright.htm
http://What-Buddha-Said.net/drops/II/The_Core_Duality.htm
http://What-Buddha-Said.net/drops/II/Magnificent_Mind.htm
http://What-Buddha-Said.net/drops/II/Highway_to_Nibbana.htm
http://What-Buddha-Said.net/drops/III/Focusing_on_Mentality.htm
http://What-Buddha-Said.net/drops/IV/Immersing_the_Body_in_the_Mind.htm

The Mind Reading Ability (Ceto-pariya-ñāna)