All the great artists have done it. Many more than once and a few like Rembrandt many time over a long life. Why? Well for one thing it is a good way to practice or try out new techniques when you don't have or can't afford a model.
This photo was taken against the back wall of my spare bedroom with one off camera flash diffused through an umbrella to one side and a reflector on the other side. I put the camera on a tripod and set the height by looking straight down the lens. I then put a marker on the floor so I stood in the same place for each attempt. I used the camera face detect autofocus feature and with a little trial and error got the framing right. I triggered the exposure with a remote release and for the flash I used TTL mode. I had to check each shot on the back of the camera but if you have a screen that can be turned to face forward life will be so much easier. Tethering to a computer is ideal and can be easily set up for most cameras. Lightroom supports tethering for Canon and Nikon. There is a workaround for Sony but Sony now has free software "Imaging Edge" available for download that allows tethering. https://imagingedge.sony.net/en-gb/ie-desktop.html
Many of the shots I took were dreadful. I looked like a rabbit caught in headlights. So I took my lead from Peter Hurley (another advocate of the self portrait) and tried his "squinch" technique of slightly narrowing my eyes. It worked a treat. Check Peter Hurley out on YouTube. He runs a business called "The Headshot Crew" and has other great posing advice.
The end result is that you'll have some fun, you'll use that flash that is sitting gathering dust, and you don't need a studio or a model. You will also have some images to practice processing techniques and you never know you might even get a winner. At the very least you should get a new profile pic.
Until the next time, go have fun