You need this to get it done:
Action DetailsRequirements and how-to articles for Steam's action:
You can promote trusted community members or add internal team members to help moderate your Steam Community Hub. (See official documentation for more details.)
Give your artwork a title (maximum of 128 characters.)
File format: .jpg/.png/.gif
Maximum file size: 8MB
Use this space to describe your artwork or what was involved in making it (BBCode formatting available, maximum of 8000 characters.)
Enter the title for your guide (maximum of 128 characters.)
Guide Branding Image
This image will represent your guide in the Steam Community. When users search, browse, or filter the list of guides this is the image that will appear next to your guide. For best results, use something that represents the theme or contents of the guide.
Aspect ratio: Square
Dimensions: Minimum of 195 x 195 pixels
Use this space to describe your guide, what makes it interesting, and what the scope is. This will appear as the description when browsing through the list of guides for this game. (BBCode formatting available, maximum of 8000 characters.)
Choose which categories your guide belongs in (e.g. Achievements, Gameplay Basics, Secrets) and the language it is written in.
The contents of your guide are split into separate sections, which will be listed in the table of contents when your guide is published. Each section has its own title and a maximum length of 8000 characters, with BBCode formatting available. You can also add images, screenshots and videos.
Select and upload images you wish to reference in your guide (upload all the necessary images and they will be easily selectable when editing individual sections of your guide.) You can select multiple files to upload at once, but only up to 8 MB at once.
File format: .jpg/.gif/.png
The title of your discussion.
The content of your discussion. (BBCode formatting available.)
Choose the sub forum to post your discussion in (e.g. General Discussions/Events & Announcements/Help & Support.)
Videos must be uploaded to YouTube before you'll be able to submit them to the Steam community. YouTube videos must be set to public and embedding must be enabled, and your Steam account must be linked to your YouTube account.