Changing colors when circular knitting

I’m trying to knit this hat right now and it’s my first time using circular knitting needles, so I was wondering if someone could explain to me how I’m suppose to change the color for the stripes. Thanks in advance!
^ that’s the hat

You can just start knitting with the new color. Don’t cut the main color since you only have to bring it up a few rows, and only cut the stripe colors when you’re done with them. You can weave in the ends of the stripe yarns later.

As you knit in the round, you’re really knitting in a spiral, so you will get a jog when you start or end a stripe. Here is a site that tells you how to avoid that if it bothers you.

you don’t have to tie it in or anything? you can just start knitting and then weave it in and it’ll stay?

Yes, it will stay. I should have also suggested that you check out Amy’s videos on connecting new yarn, in the Basic Techniques, More section.