Things to do:
- select the "Add Media" button on the top left corner above the text edit field
- make sure you're in the "Upload Files" tab in the top-left corner
- click on "Select Files" and choose the picture you would like to insert
- In "Attachment Details" on the right, you can edit the title of your picture, add a caption and a description
- In "Attachment Display Settings" just underneath, select the alignment and size of your picture
- Select "Insert into post" at the bottom.
For further instructions please click here.