See below, this explains the steps on how to use all the features on Cloud Caption:
1) Tap Select button and choose a photo first (of course).
2) The cloud bubble appears automatically on top of your photo, so tap your screen to position the cloud bubble and also tap the cloud size buttons to make your cloud bubble bigger or smaller on your photo, however you wish.
Note you can also tap the change button to change the cloud bubble type, keep tapping it to toggle through all the different ones as they appear on your photo. You can also tap fade to make it lighter or darker if you want it see through.
3) Now assuming you tapped the screen to get the cloud bubble exactly where you want it and exactly how you want it to look, you "Apply" it by tapping the apply button.
4) Now the text box shows automatically at the top, tap in the text box and begin typing your text caption to put in the cloud bubble. When you tap the box, the keyboard automatically appears so you can type your word, etc.
5) Click done on the keyboard and your text now shows on your screen, so tap the screen where your cloud bubble is located to move your text into the cloud bubble. Note you can tap the Text Size button to make text bigger to smaller to fit your cloud however you want. The cloud wont move since you applied it earlier, so now you are doing just the text on the cloud.
6) When your text is ready, tap Apply button to apply it as it shows. If you want to add a second line of text now, you can also do that, just tap back into the box at the top and type another word, line, etc, and click Done on the keyboard when ready. Follow the same instructions again to tap the screen and position your 2nd line of text on your cloud bubble.
*Note that you dont really have a return or end of line needed, as you just apply your first line of text and Apple it, then type in a 2nd line and position it on screen where you want it, then apply that, etc.
7) Tap Save to save the photo with your cloud bubble and text caption(s).
8) Note that if you want multiple cloud captions on 1 photo, after saving, just tap select and choose your new saved photo and you can add another cloud bubble on top of that photo.