Question regarding demand schedule and equilibrium consumption Please refer to the two images posted at this link: http://imgur.com/a/si3ko

Referring to Page 2, I'm not quite sure what the author is trying to say regarding the two bracketed portions. Considering the first bracketed portion, when the author says "purchased less than Q0", is the author still referring to a point on the demand schedule line? Also referring to the first bracketed portion, how do we know the consumer "value additional consumption more than its cost to her", and thus purchase more? How do I represent all these graphically?
Yes, he is referring to a movement along the demand line. If the individual purchases less than $Q_0$, than the demand line would be higher than the price for quantities for $Q_0$, this means that the individual values consumption more than its cost (its price). Graphically, you just need to show that for a quantity less than $Q_0$, the demand line is higher than the price, i.e. the individual values consumption more than its cost.