Uploading a Skin to the Workshop If you would like to upload your skin to the workshop, you must abide by the rules and guidelines. Otherwise, you may not be allowed to upload it. The requirements of uploading your skin to the Steam Workshop are as follows:

• Your skin folder must contain a file named steam_workshop_preview.png (file size must be under 1MB). The file will be used as the thumbnail of your skin.
  
• Your Steam account must be eligible for uploading. If you have issues uploading your skin to the workshop, this article may be one of the reasons.
  
• You must have agreed on the Steam Subscriber Agreement.

We suggest putting the gameplay of your skin in the steam_workshop_preview.png so the players can see what the skin would and the file size should be under 1MB regardless of the image’s resolution.