A crucial element of doing business with someone is trust, and a way to gain that trust is to show your face on your profile. You don't have to be a model you just need a smile to improve the trust with potential clients.
To increase your chances even further, you can take a professional picture of your yourself.
Do's
Select a simple background. Pick a background that will not have a tree, street sign or light post sticking out of your head. Make sure there are no cars or other people in your shot as well. Ideal backdrops are solid-coloured concrete walls. Simple textures also can be nice backgrounds too.
Dress appropriately, men should wear a shirt with a collar that is not wrinkled, if you have a suit that's even better. For women it's appropriate to wear professional well-fitted clothing., that is not too tight but not too loose. For all sexes, long sleeves are better for headshots than short sleeves.
Headshot photos should frame your face and the upper part of your torso.
Look at the camera with a confident smile :)
Take multiple photos and chose the best one.
Ask a friend or a family member to take a photo of you, and make sure the photo is taken at your level.
Dont's
Don't take a photo of yourself with an inappropriate background like a washroom.
Don't submit photos of yourself with no shirt or with messy hair.
Don't submit blurry photos or photos of other people
Don't wear shirts with graphics or any kind of messaging.
Example of a Good Photo
Example of a Bad Photo