How do i write my name in Korean?

This was answered here before as 제이든 (jay-duhn). (assuming Jaden rhymes with "pay done").

Be aware though, that Koreans will probably try to pronounce the name the way it is written and say "자덴 (jah-den). You'll just have to correct them.

Actually the ㅐ vowel would have more of a short-a sound more similar to the English word "apple"

In this case to get that long-a sound, it would be written 제이덴 Pronounced "chei-den"

Koreans don't pronounce a hard "J" sound at the beginning of a word, so instead it would have more of a "ch" pronunciation

It would probably be written as jae-den, or in hangeul (their alphabet/writing system) = 재덴

If your name is pronounced Jay-dehn, then that's how they would spell it.