*Disclaimer: I have an android and dont know how to do this on an Apple.*
I am aware that there is a werid thing with the keyboard where it adds a space after every letter. I don't know how to fox this, I'm sorry.
First your going to want to copy and paste the whole alphabet. Easier to do letter by letter, but you can add the whole alphabet then delete the unwanted letters after.
1. Open Settings
2. Scroll down to "General Management"
3. Select "Language and Input"
4. Select "On-Screen Keyboards"
5. Select "Default Keyboard"
6. Select the mini settings button.
7. Scroll down to the bottom and select "Text Shortcuts"
8. Tap the plus to add the alphabet in.
9. Select what you want the shortcut to be. I do double letters (ex.aa=⏃)
Any additional questions, ask them here! I'll respond as quickly as I can.
ONLY DO ONE LETTER AT A TIME!!!