In order to knit longer (into our dotage), and additionally to give greater ability and more options it can be very worthwhile to train one’s less-dominant hand to operate the yarn. Regardless of which hand you favour, there can be advantages to becoming proficient with either hand. Regard this as knit-training!
My suggested training regime is to establish a comfortable number of stitches on a 40 cm/16″ circular needle with a medium weight yarn (to suit the size of the needle). Begin this with your favoured knitting hand to get you started, build up a couple of rounds of fabric. Now observe which direction your customary working hand wraps the yarn around the needle.
Re-position the yarn into your other hand and replicate the direction of wrapping. Don’t worry, it will feel funny. (Just think how many millions of repetitions of this action your ‘best’ knitting hand has under its belt? It is only fair to give your other hand a chance to get used to this action.)
If you encounter twisted stitches on the needle on subsequent rounds, you have altered the direction in which you are wrapping the yarn around the needle.
Once your newer hand is getting the hang of things, practice working alternating stitches, using two different coloured yarns one in either hand.
The ability to KNIT with both hands and two yarns at once will be all you need to work the majority of two-colour-per-round projects done in the round. There are easy weaving-in methods for catching in long floats without twizzling your yarns or the need to let go of your yarn and needles that can be learned later.
Once you have knitting with both hands under control, try purling!
There is an entire chapter on Becoming Ambidextrous in: