THey are using screenshots or animated gifs, and using HTML and CSS coding to place them on their profiles.
YOu can do this a few ways:
You can hire a designer to create this for you. Pro: You dont have to do anything! Con: everytime you need to add a video you'll need them to update it for you. There are plenty of camgirls who offer this as well as members.
You can learn the basics yourself. We have profile help in this forum, and there are several blogs etc with helpful advice.
You can buy a template service - you still need to do some of the coding (understanding where to put the code and how) but you don't have to create it all yourself. You do the updates yourself and you only need to buy it once.
You can use a service like camgirltoolkit.com where you do NONE of the coding and it generates the HTML and CSS for you. (full disclosure, this is my website). You pay a low fee per month, and never have to go to a designer to make updates or changes.
You can seek out people that are willing to help for free..there are a few members out there that will do profile design for you for free. This comes with the same issues about updating however.. and if they go awol you're screwed if you dont know how to work what they did.
I hope this helps?