He could use a simple cloth. Just a plain piece of fabric wrapped around his face, like a ninja in a hurry would do. This is a very basic and practical way that is often seen in traditional ninja - themed stories.
Perhaps he's trying to protect himself from some kind of danger. There could be an enemy who is looking for him and by covering his face, he can avoid being detected easily. It could also be a part of a new jutsu or power he has discovered where covering his face is necessary for its activation or control.
In certain fanfictions, Naruto's lightning power is used in a more strategic way. He might use it to create diversions. For example, he could make a bright flash of lightning in one area to distract his opponents while he moves to a different position for a surprise attack. He could also use it in combination with his shadow clone jutsu. The clones could be made to carry a small amount of lightning power each, and when they are attacked or dissipated, they release a shock that stuns the enemy.
It could be a new character created specifically for the fanfic. Maybe a rogue ninja from a far - off land who has a vendetta against Naruto. This antagonist might be after Naruto's power or trying to stop him from achieving a certain goal.
One way is through his Jinchuriki status. The Nine - Tailed Fox inside him has a primal connection to nature in some fanfictions. The fox's chakra, which Naruto can access, is linked to the natural forces of destruction and creation. Another way is his friendship with animals. Naruto is sometimes shown befriending forest creatures, which shows his harmonious connection with nature.
There are fanfictions where Naruto teams up with other powerful characters like Jiraiya. Together, they come up with a plan to trap Orochimaru and then Naruto delivers the final blow. Naruto might use his Sage Mode skills, if he has them in that particular fanfiction, in combination with Jiraiya's knowledge and power to outwit and defeat Orochimaru.
One way Ino helps is by being a source of emotional support. Her friendship with characters like Sakura can be a stabilizing force. In some fanfictions, she might offer advice on relationships or personal growth.
One possible reason could be that he is on a secret mission and doesn't want to be recognized. He might be infiltrating an enemy organization or spying on someone. Another reason could be that he has some new power or mark on his face that he wants to keep hidden until he fully understands or masters it.
In some fanfictions, Naruto is the Nine - Tail Fox in a spiritual sense. His mind and the Nine - Tail Fox's are so intertwined that they can communicate and act as one without the need for the usual forms of control. Also, he could be seen as the physical manifestation of the Nine - Tail Fox's will, where his actions are guided by the Nine - Tail Fox's instincts and desires.
In some fanfictions, Kushina could be sealed in Naruto during a moment of great sacrifice. For example, if Naruto was in a near - death situation, Kushina's spirit might choose to merge with him, sealing herself within him to save his life. Or perhaps there was a dark magic user who tried to steal Kushina's power, but instead of losing it, she managed to redirect it into Naruto through a self - imposed seal.
Naruto could carry Itachi's ideals. Itachi sacrificed a great deal for the village, and Naruto, who also values the village deeply, could take on those ideals. He could start promoting peace in the way Itachi believed in, by trying to understand the enemies' motives and finding non - violent solutions first. This would be a great way of carrying Itachi within himself, in a more philosophical sense.