So. You are not a man, but you have male characters trying to tell a story in your head. How do you translate that to the page without losing their ‘manliness?’ Good question.
Relax
First, take a deep breath. For all the jokes and slights about men and women being practically different species, that’s just not true. People are people, full stop. The primary differences you’ll find between men and women are created by culture, and with some elbow grease and determination anyone can dig into the how’s and why’s of a stranger’s thinking process. You’ve doubtlessly written about someone who has a different religion, ethnicity, culture, or even entire world. Writing from another gender’s perspective may broaden your mind, but it certainly won’t break it.
Thought Process
The biggest challenge you’ll face as you write a man is nailing how he thinks. There’s a lot of technical craft and tricky skills that go into creating good prose, and a LOT of prose stems from your characters’ thoughts, feelings, and expectations. Begin with expectations, both the character’s and his society’s. Men in your culture behave differently from women because they’re trained to, and that all boils down to goals and aspirations, something you should already understand intimately from your time developing plots.
Once you know what your male character needs or wants, examine his options. For example, men don’t enjoy the same freedom of expression women typically do, especially in public. They are expected to ‘stand by’ their decisions, and making an incorrect decision, or being proven wrong, seriously challenges their sense of personhood and self-worth. Men feel the same things women do, but the way they deal with and move on from those feelings looks different due to the tools available to them.
Language
Words are a writer’s primary tools, and you need to use the write ones to speak as a man. It’s simplistic to say that men are just more direct than women, but it’s a place to start. Again, this is a deeply cultural issue. If you have the time, do a little academic research into the linguistic differences between male and female communication. They utilize different vocabularies, pronouns, and much more to navigate tricky situations, express feelings, or get out of trouble.
Behavior
We’ve all heard about little boys throwing rocks at girls they like. Maybe the boys in your written world do this, and maybe they don’t, but they’ll probably do a lot of things their female friends just won’t understand. Fill a few pages with memories of weird things boys you know have done – friends, coworkers, family – doesn’t matter. Ask yourself why they did them, look for patterns, and apply the logic you find there to your own characters.
Share the Good and the Bad
You know how awful it is to read a story about a woman that’s written by a man and she’s just weirdly too good or too evil, like her gender has bleached away part of her character? Yeah. Make a note: don’t do that with male characters. If there’s something most men do that makes you uncomfortable, don’t try to bury it just to make yourself more comfortable. Dig into the weird, the bad, and the sweet. Get a full character, and don’t let their gender create blank spots as you idolize or demean them
Ask, Listen, and Read
The best way to understand men, like any other group of people, is to listen. Talk to men in your life and ask questions about how they’d react to being stranded on an island, swarmed in the zombie apocalypse, or ditched by a girl they thought had romantic feelings for them. They won’t all answer the same way, but you’ll find rhythms and patterns that you can echo in your character. Read, too. Find books about cultural differences, linguistic differences, etc. It will help a LOT.
Never forget: editing is magic. Write your story with whichever character foists his POV on your brain and worry about the details later. You can always perfect his dialogue and thoughts in revisions. Male beta readers will help! Don’t let a different point of view stymie your muse. You’ve got this. Now go write a thing.