After you have uploaded a picture, there may be a chance that you will want to crop or re-size it to make it look better; you may also want to change what portion of the image shows up in the thumbnail. The following steps will help you with these goals:
1)In the media library, click on the image you would like to edit. On the next screen click the “Edit Image” button underneath the picture.
2)Select whether the changes you are about to make should apply to the full image or the thumbnail.
3)Drag a box, on the image, over the part that you would like to keep (or show up in the thumbnail).
4)Click the crop icon above the image. This will then show you what the cropped image looks like.
5)Once satisfied with the cropping, click the save button below the image. This will take you out of the edit page.
6)Finally, click the update image button and you are done.
However, if you are editing an image that you have already put in a post you will need to take one additional step. Go into the edit page for the post and remove the current image, then insert the image you just edited. It should carry over the previous caption/settings. As always, check the post to make sure it looks good and you are done!