How do I compose Messages on iOS ?

How to Compose A Text On An IOS Device:

You can compose messages by following these instructions:
On Talkatone, tap on the Contacts icon, tap on your contact, tap on the Compose Text icon on the lower right corner. 

Alternatively, tap on the keypad icon, dial the phone number, tap on the Compose Text icon on the lower left corner.

Here is a video showing these steps for your convenience.