How To Start Off With A Language Partner

I'm here to take lessons with teachers, but I'm also looking for language partners. How do I start once I find someone? I'm not a great conversationalist in my native language, so I'm kind of lost. Any advice to get things rolling? Also, with Japanese I should be able to start smoothly. I can read kana and ~600 Kanji, and I should easily pass JLPT 5 this December. But my Mandarin is awful. I am at the level of talking about family members, hobbies, and saying that I have done something, like to do something, would like to do something, will do something, and that's about it. Do you just heavily rely on something like google translate to get started, or try to only work with what you know?