Try writing the English text along with the Korean text. That way you have a better chance of attracting people who are really focussed on learning your native language in exchange for Korean.
I would avoid contentious topics like politics or religion (at least initially), perhaps you could describe the scenery and city life in Singapore. I always find the gold markets in Singapore a dazzzling site, with the golden gleam filling the night sky. Be patient and keep notebook entries short, longer ones are problematic to correct. Good luck !