Go to selection tool go to ellipse and make a circle or something circular

Next add the colors of the rainbow 🌈

Next blend it using the blending tool blend it until it becomes some thing like this

Next add the highlights and change the opacity to around 50 percent

 

Use another layer for the highlights

Add the background and your done

To make it more "transparent like" you can use the soft brush and use the color you used for your background to do this make sure its on a another layer

Don't forget to deselect the selection tool

Done

💕and also thank you for supporting me