u've created a super demo, and now you want a Fiverr gig image that is equally good,. So you get some photos taken, and choose a headshot. Using the select tool in your favorite photo editor, you select out the background, because it's distracting, and replace it with something more impressive looking. But something seems wrong! Despite your having tried to be careful, it looks as though your head was cut from a magazine with a pair of dull scissors. Something looks very unnatural about it.
The problem is you've created "helmet head." In its natural state, hair isn't perfect. It has a feathery edge to it. What has happened is that you've cut it smooth, and it no longer looks like people are used to seeing hair. The result is artificial and and has a bizarre feel to it.
There are several solutions to the problem. for one, you can be more meticulous in your "cutting. Another is that you can use a blur tool to soften the edge. That helps a lot. Another is to use more advanced techniques like are described here:
And yet another is to hire a Fiverr person to help you. There are some real "cut out magicians" who do this kind of work all day long, for a pittance. While you're at it, have someone design a logo for you, and do up some really awesome typography as well. My goodness, spend a few bucks...it's worth it to hire people who specialize in this stuff, especially at Fiverr rates. The gig image is a very important part of your Fiverr marketing