It doesn't need much to start a broadcast: A PC or laptop, a decent internet connection and a webcam are enough to try it out, but you should always invest your first money into improving your equipment to boost the viewing experience for your fans.
First of all you need a PC or laptop with a browser that supports Adobe Flash Player. The most recommended browser would be Google Chrome, it comes with Adobe Flash Player built-in and updates itself and the Flash Player automatically. An alternative is Mozilla Firefox, but you will need to download Adobe Flash Player manually. You don't need an expensive computer with a quadcore processor and tons of RAM, if your computer is capable of handling a Netflix stream, you'll be fine.
It’s very important to have a decent, stable internet connection to have a smooth stream and a crisp picture, these are some examples of minimum upload bandwith requirements:
480p or 640×480 (2000 kbit/s or more)
720p or 1280×720 (3000 kbit/s or more)
1080p or 1920×1080 (6000 kbit/s or more)
If your ISP connection is decent, but you still run into connection problems, make sure to have a stable WiFi signal or go with an ethernet cable connection right away.
To look nicely and provide a good video stream you need a decent webcam. Any webcam will do, but not every webcam can handle high resolutions and has decent auto-focus. There is nothing more annoying than being out of focus or seeing the process of a webcam attempting to focus you constantly. Professional broadcasters might want to have a look at remote controlled webcams with pan, tilt and zoom options. You can even give your tippers control over your webcam with these.
Recommended models are:
Many broadcasters prefer to have their microphone turned off, but communicating with your viewers and natural sounds will appeal to your viewers. In most cases it’s enough to use the internal microphone of your laptop or webcam. If that is not enough for you and you want to please your viewer’s ears a condenser microphone is the way to go, it’s used for radio and podcasts and will filter background noises. Popular options are the Blue Snowball, the Blue Yeti USB microphone and for professionals the Shure SM7B.
Good lightning is essential, the amount and positioning are key. Your best choice would always be daylight, it is very bright and gives a natural color. When broadcasting with daylight it is important to not have it coming from the back to disturb the broadcast. The main light should always come from the front where your webcam is positioned and minor from the sides, your background should be lit, but no beams of light should point from there. If no daylight is available you can use your standard room lights, they tend to be on the warm or cold side, though, and will give a wrong coloring. A professional option would be the use of 5500k (the color temperature of daylight) lightbulbs and softboxes to avoid hard light and shadows. A cheap kit would be the one from Neewer, it comes with stands, sockets, bulbs and softboxes and is ready to use.
A wireless keyboard with built-in trackpad gives you the freedom to move around your room and pose in several position while still being able to communicate with your viewers. If you broadcast from a laptop you will not need this, but with a desktop computer or a HTPC connected to your TV this will greatly help.