According to HLN:
Thursdays proceedings will be run similarly to Wednesdays aggravation phase. It will be a like a miniature trial, with some slight differences.
The defense will go first when it comes to opening statements, and the defense will also get the last word with a rebuttal closing argument.
The sentencing phase is the defenses opportunity to ask the jury for leniency and present evidence supporting why Arias should be spared from the death penalty. Witnesses may include Arias friends and family. Arias could also make a statement to the jury pleading for her life to be spared.
Alexanders family members may take the stand for the prosecution to give victim impact statements. The familys statements will likely be emotional as they describe their loss.
After closing arguments, the jury then deliberates for a third time to determine whether Arias should be sentenced to life or death. Their decision must be unanimous. In the case of a deadlock, a mistrial would be granted and a new jury would be chosen for this phase only.