When you are in edit mode, select a photo capsule from the top right hand side list of options.Put it in place where you want in your hub. You will see arrows, choose the arrow pointing to the LEFT, this puts your capsule to the left, leaving the other half free for putting in a text capsule.
Drag the arrow that is on the far side of your hub (in green I think) to about level of the photo capsule. Release your finger and you will see a list of capsule options, click text and it should then take up the other half of the page, sitting next to your photo hub. If it drops in above, just click the down arrow and it will be side by side.
It is a great tool and you can also find it in the learning center with other hub structure and capsule info. Hope this was beneficial and easy to understand! Best of luck!