[Tutor] Columnar Transposition Cipher question

[Natalie Kristine T. Castillo]

Hi, I need help on how exactly to solve this:

To send secret messages you and your partner have decided to use the  
columnar function you have written to perform columnar transposition  
cipher for this course. You have received the ciphertext  
EXLYHILOSHOOAETU from your friend. You two decide to use the keyword  
MARS. What message did your friend send you? Show your steps and do it  
by hand.