Most character perspectives are revealed as part of the overall process of revealing character, see 103 on engaging and revealing characters, but POV characters have the added challenge of conveying the details of the story while also remaining true to their own perspective.
Consider Sherlock Holmes. Sherlock cannot be the main character; he knows too much. Audiences need Watson, who can observe markings on a door, or footprints on the ground, without realizing what they mean, preserving the audience’s opportunity to try and solve the mystery themselves.
Familiar & Foreign
One of the challenges of POV characters is maintaining perspective. What is the character familiar with? What is strange or alien to them? Every detail needs an underlying reason for the character to notice it.
For example; what if a red car drives down the street. One character sees “a Pontiac GTO coasting down the street,” while another simply sees “a car drove by.” What if the car is an annoyance, “barreling down the road with all the grace of a whirlwind, kicking up dust in its wake.” The key is to create a reason for the POV character to notice, and filter details through their perspective.
Most characters focus on something because it’s unusual, engaging, desirable, frightening, distracting, annoying, or symbolizes a goal. If a detail doesn’t fit, the author can change the character, or change the scene.
Simple & Complex POV
Some stories, such as fairy tales or children’s stories, exist to teach. The hero is clearly right, villain is clearly wrong, and the story demonstrates why through the outcome. These are simple stories, easy for audiences to understand.
Other stories are complex; exploring questions about the meaning of life, God, or morality, to name a few. Complex questions can help engage the audience, but they also require a more impartial representation. Characters should be conflicted, and at least one character should propone each of the major perspectives on the subject.
For example, if the protagonist believes that there is no God; that life is simply a series of experiences without meaning or purpose, then at least one character should believe in God and defend their faith, while a third character can propone the idea that life has meaning regardless of whether or not God exists. Throughout the story these three perspectives will clash, with each character expressing and defending their position, and in the end the audience will be left to decide for themselves.
Simple stories are easily understood and often relaxing, while complex stories challenge the audience to question what they believe.