Here are a few things you should know before you upload the content.
1. Make sure the pictures are authentic content by you, and upload pictures without watermarks.
2. Make sure the pictures are not over edited. Try to preserve the natural colors as much as you can.
3. Do not upload B & W pictures.
4. Upload more of Landscape Oriented Pictures. Portrait ( Vertical) Oriented Pictures have low sellability.
5. Update the metadata information and location information to the most accurate possible.