How to translation on Kato platform after I've claimed a task?

Hi All:

This is my first time to translate tasks on Kato platform. I have already claimed a translation task on Kato platform. But on the page of “my claimed task page”, I click the green" translate using kata TM", it brings me to the MateCat website (two options for using MateCat). But I couldn’t find where and how to translate my claimed task on MateCat. Please help to clarify this!

Thanks!