Help creating a poster

[Aromabish]

Hello, I'm kinda experienced with photoshop, but for some reason I can't make something decent like poster for a game.
We are currently developing one, so I'm trying to create a poster. If someone can share their experience in creating this, I would definitely appreciate it.

 

[Somethingshenny]

In my opinion, the poster should match the genre of your game.

For a sci-fi/fantasy theme, you can take a reference from the popular movie with the same genre (e.g LOTR, Star Wars, or any movie you find appealing).