Changing yarn

I’m a beginner and working on a scarf in ribbed stitch–53 stitches [3K, 1P] K. It’s going well and I am almost at the end of the first ball of wool. How do I transition to a new ball?
Thanks

Unless it’s superwash, I’d use a felted join. http://www.knittinghelp.com/videos/knitting-tips

Scroll down on this page and there are videos with different types of joins.

http://www.knittinghelp.com/videos/knitting-tips

Thanks for the quick reply. Since my ‘wool’ is 70% acrylic and only 30% wool, I will try the Russian join.
Thanks again!