Maybe this link will help you get started.
https://steemit.com/steemit/@steemitguide/tips-on-how-to-edit-and-customize-images-via-steemit-s-raw-html-editor-add-links-source-reliable-image-hosting-services-and
Maybe this link will help you get started.
https://steemit.com/steemit/@steemitguide/tips-on-how-to-edit-and-customize-images-via-steemit-s-raw-html-editor-add-links-source-reliable-image-hosting-services-and