How to join wool with leftover tiny balls

Hi, I’m knitting a throw for the lap with leftover yarn. I always add a new colour on the right side of my knitting (cast on tail on my left). I find now that I have only tiny balls of wool one colour isn’t enough to either finish the row or get back to right side to start another… row.
How can I make it work so that the join is in the right place if it is possible?
TIA

There are several different joins depending on the type of yarn and the colors.
Spit splicing works for wool and overlapping yarns for a stitch will work well for the same colors. You can even drop the old yarn and knit the next stitch with the new strand then cross the yarns on the back to close up a hole when you weave in the ends.
Russian join works for joining either the same or different colors.

You can just as easily join new yarn when working the wrong side. You can just purl the next sttch with the new yarn.
Or maybe I misunderstood the question.