Profile pictures, Icons, Avis, no matter what you call them they are very important to the first impression of your brand. This is normally what people remember you by whether it be a business logo or picture of yourself. It is important that you have a high-quality image to put a face with your business, brand or service.
For those with a business or entity separate from yourself, the business logo will suffice. Just be sure that the image is clean simple and easy to identify with.
With a personal brand be sure to make your icon relevant to your craft. A general business headshot or three-quarter shot is clean, professional and good for just about any business. If you are a doctor, wear a lab coat. If you are a karate instructor, where gi. Wearing a suit and tie is best for men while a blazer over a blouse is good for women. If your profession calls for you to dress down by all means do so.
A three point lighting system is the typical style for business photos at a studio. These sessions range from $20-$75. Some choose a particular side of their profile that they like. The shots are typically taken with the subject sitting on a stool but standing is also an option. The typical background color for business shoot is gray or brown. For those in the entertainment industry a white backdrop is popular. Ladies and gentlemen should have make up and hair ready.
If you are unable to get a professional headshot, have someone take a picture of you in a professional setting. Outdoor photos are also an option. Either way a blurred background will help draw the attention to the subject and not what is behind them. Always smile. People gravitate to those that smile.