You should Sign in - you can do it with your twitter and facebook accounts (do it with both) and make another accounts with your emails too, it’s easy, all in English ^^
It’s in Korean, but it’s pretty simple. No login needed. Just click the yellow button which reads “투표”. You can vote once a day.
Same thing than the one above. It’s in Korean, just click on the star next to SUJU’s name. One vote per day.