Questions & Answers about Bu siyah gömleği kendin nasıl ütüledin?
How does kendin mean "yourself" in this sentence?
The base word for "self" is kendi. To say "myself", "yourself", and so on, Turkish adds standard possessive suffixes to it. Here, the 2nd-person singular suffix -n is added to make kendin (your-self).
Could I just use the word sen (you) instead of kendin here?
Not without changing the meaning. If you used sen, the sentence would simply mean "How did you iron this black shirt?". Using kendin specifically emphasizes that you did the ironing yourself, without anyone else's help.
Why is the word for shirt written as gömleği instead of gömlek?
Two things are happening here. First, because the shirt is a specific direct object (you are pointing out "this" black shirt), it needs the accusative case suffix -i. Second, adding this vowel suffix causes the final k in gömlek to soften into a ğ (soft g), becoming gömleği.
Is there a reason nasıl (how) is placed right before the verb?
Yes! In Turkish, the most emphasized information is placed immediately before the verb. Question words like nasıl naturally belong in this "focus position" right next to the action they are asking about.