One way is through detailed descriptions of his physical reactions. For instance, if he's been stabbed by a lightsaber, describe how he clutches the wound, his face contorted in pain, and his breathing becoming ragged. This makes the reader really feel his physical agony.
To show emotional pain, the writer can have Luke withdraw from his friends and isolate himself. He might stop talking as much, and when he does speak, his words could be filled with sadness or anger. The writer can also use internal monologues where Luke reflects on what's causing him pain, like memories that keep resurfacing and tormenting him.
Using the reactions of other characters around Luke can also be effective. If Leia sees her brother in pain, her concern and attempts to help can highlight just how serious Luke's situation is. And if Luke is trying to hide his pain from others, that in itself shows his strength but also the depth of his hurt.
The writer can focus on Naruto's emotions. Show his shock and disbelief when the hurt occurs. For example, if Sasuke attacks him, describe how Naruto's eyes widen in horror, unable to believe that his friend would do such a thing. Use internal monologue to let the readers know how broken Naruto feels inside. Another way is to show the physical pain in detail, like if Sakura uses her medical skills to harm rather than heal Naruto, describe the pain as it courses through his body.
Some writers will use symbolism to show Sam's pain. For example, if he's been hurt by a dark magic spell, they might describe the darkening of his eyes or a shadow that seems to follow him. And in terms of his emotional pain, they could compare it to a storm brewing inside him, with his thoughts and feelings churning like thunderclouds.
Some fanfictions might involve Luke getting hurt because of a betrayal. He trusts someone, perhaps a new ally, and they end up turning on him. This not only causes physical harm but also a great deal of psychological damage. He then has to figure out how to deal with this betrayal while also trying to stay true to his Jedi values.
A third theme could be the exploration of the Force. His injury might lead to new insights about the Force. Maybe he discovers a new way to use it to heal himself or he has visions related to the Force while in pain, which then changes his understanding of the Force in a deeper way.
The writer can use descriptive language. For example, describe Aang's facial expressions like 'Aang's eyes, usually full of life and hope, were now dull and filled with sorrow. His lips quivered as he tried to hold back his tears.' Also, show his body language such as slumping shoulders and a slow, heavy gait. Another way is through his actions. He might withdraw from his friends, spending more time alone meditating or just sitting quietly, lost in his thoughts.
To effectively portray Batman crying, the writer should consider the context that leads to it. If it's due to a loss, describe the build - up of emotions before the break. Maybe he tries to hold it in at first, his jaw clenched and his eyes blinking rapidly to keep the tears at bay. But then something small, like a memory or a memento related to what he lost, shatters his resolve. The writer can also use the reactions of other characters around him. If Alfred is there, his look of concern and sadness can further emphasize Batman's emotional state.
The writer can describe her physical pain in detail. For example, if she has a wound on her side, describe how it throbs and limits her movement. This makes the injury seem real.
The writer can describe her physical state in detail. For example, if she has a cut on her arm, describe the blood seeping out, the pain she feels as it stings. Also, show her reaction to the injury, like her trying to hide it if she doesn't want to show weakness.
Writers can also use the power of dialogue. Let the Altair kid talk about their pain, or have other characters notice and comment on it. For instance, a friend could say 'Altair, you seem different since that incident. Are you okay?' This helps to bring the hurt and scars to the forefront. Another way is to use symbolism. Maybe the scars are not just physical but represent something deeper, like a broken trust or a lost innocence.
Show his internal thoughts. Let the readers see what he's really thinking and how it differs from what others think of him. For example, when he's creating a new piece of tech, have him worry about how it will be misused even though others might assume he's just doing it for fun.