When you're using the collage layout for your images, the images you upload will load into the collage from left to right. When you're choosing images to use in your collage, pay attention to the orientation of the images (horizontal/landscape or vertical/portrait) in the collage layout diagram. 

You can drag and drop your images to change their order after you upload them to fit into the collage better. Additionally, you can click on an individual image and change the focal point to make sure the subject of your image displays on your live blog post. Keep in mind that the collage layout may crop your image if it is a different proportion than the space in the collage for that image.

See the diagram below for a visual representation of how images are loaded into the collage.