How do you add these to your maps, the right way?

https://www.youtube.com/watch?v=AkQn1pIZdY4

thanks bro I've probably watched it twice as much as anyone. I wondered if lakes would be done differently than how Ninjanic did it. He also doesn't mention rivers but I contacted him directly and he helped me out.

I'd like to do rivers by drawing a line, then change the width of that line, then convert it to path, and cut it out from the land. Just like the lake but a bit different shape.

hm. thanks man I appreciate your help.