How to carry the yarn in stripes?
I hope you were able to figure something out! If you're talking about carrying the red yarn up as you knit the green stripe, you could do something very similar every other row on the right side as you did when catching your floats; twist or wrap the red yarn around the green once before you begin working the row. This is (slightly) better hidden from the right side when you're slipping the first stitch too. You may see a little of the red on the edge of the object, but I've never had enough to bother me.