I was going through some notes that I have and found this handy hint.
Knitting Jogless Stripes in the Round:
(This only works if you have a minimum of 2 rows per stripe)
Knit 1 round of the new colour.
When faced with the first stitch of the second round: pick up a loopof the first colour from the preceding row an place it on the left needle. Knit together both the first stitch of the new colour and the picked up stitch of the previous row. Continue knitting around.