How can i change the color of my name?
Not sure if this still works but yes, you're right. Using /scoreboard teams add {{YOUR TEAM NAME}} & then /scoreboard teams option {{YOUR TEAM NAME}} color {{COLOR}} should turn your name to your chosen color.
If you're having trouble finding exact color names, I've grabbed a quick list of them from the minecraft wiki.
Enjoy!
By the way, the only place you would use /nick would be in a server that has the plugin.