I was looking at the name [name_f]Katelyn[/name_f] on Nameberry, and decided to search for different spellings. I found over 40 different ways. What you you say is the most correct spelling? Would you spell it with a C or a K? Below are some that looked right to me.
[name_f]Katelyn[/name_f]
[name_f]Kaitlyn[/name_f]
[name_f]Caitlin[/name_f]
[name_f]Caitlyn[/name_f]
I would spell it [name_f]Caitlin[/name_f].
Definitely [name_f]Caitlin[/name_f]. It’s the classic.
I intentionally started typing before I read anything so I could get my real thoughts without being biased towards one spelling or the other. I meant to type [name_f]Kaitlyn[/name_f], but I ended up tying [name_f]Caitlyn[/name_f], so go figure. 
I’m honestly surprised by my own response because I typically hate Ys-for-Is.
Automatically, I write [name_f]Caitlin[/name_f]. Secondly, I’d say [name_f]Kaitlin[/name_f].
The classic/original spelling is [name_f]Caitlin[/name_f]. But, no matter how you spell it, you will always have to be correcting people (I say that as a [name_f]Kaitlin[/name_f] myself 
).
[name_f]Caitlin[/name_f] is the only one I like.
[name_f]Caitlin[/name_f] is the original from my understanding, [name_f]Katelyn[/name_f] is the second most common I’ve come across. I quite like [name_f]Katelin[/name_f] myself. But as someone else said, you’re going to get misspellings whichever one you choose (I’m a [name_u]Clare[/name_u] who usually gets misspelled [name_f]Claire[/name_f] as its more common, but sometimes people will assume [name_u]Clare[/name_u] or [name_u]Clair[/name_u] without asking too)