You can search them in the "Language Exchange" or they will find you and add you. Example, I wil add you so you can see.

Just click the language exchange button and search for someone. Once you find someone, you can follow them, if they follow you back, then you can message each other.... on some accounts at least. That's about the closest thing there is to "adding" someone on this new version of italki now :/

你可以点击：语言交换，然后输入你想学的语言以及你会的语言，点击搜索，然后就可以加好友了。