What You Need
For webcam chatting, you need fast internet, a computer and a webcam. That is basically it. Next to that you will need a bank account, a valid passport or ID and you have to be at least 18 years old. Obviously a secluded place with some privacy will also help. ;)
First of all you need a stable fast internet connection. Because you will be transferring data to the internet, the most important parameter will be the upload speed.
Usually if you have an internet connection at home you have a high download speed and a lower upload speed. For instance and old fashioned ADSL connection may have a download speed of 2 Mb/s (2,000,000 bits per second) and an upload speed 256 kb/s (256,000 bits per second). More up to date connections may have 8Mb download and 1 Mb upload speed, or 20 Mb download and 2 Mb upload or faster. You can check your subscription for the details of your connection. There is no fixed minimum upload speed you need to have, but higher speeds will give more possibilities. On a slow connection you may only manage to broadcast a low quality cam image with slow changing pictures and no sound. On a faster connection you can broadcast a HD quality signal with good video quality and good sound. On even higher speed connections you can broadcast multiple HD quality streams with good quality sound. Investing in a better internet connection may be the first thing you want to do to improve the quality of your broadcasts, and with that the posssibility of sufficient earnings.
Webcam chat sites do not require a lot of performance from your computer. You need a computer for it, but not a very big one. Any new pc or laptop you buy in a store today will have sufficient performance to allow for webcam chatting in high quality. Some computers may have performance problems that come to light when you try it, but they are the unfortunate exceptions. In principle any decent pc or laptop of less than 10 years old should be powerfull enough to do it. If you can play youtube videos and use skype or yahoo videochat you should also be able to use the computer for webcam chatting. Both a normal (wired ethernet) cable network connection and wifi should not cause problems for webcam chatting. A big screen is convenient if you want to be in several chatrooms at the same time, but is not absolutely necessary.
MS Windows will surely allow you to chat on most, if not all, websites. On iOS you will need a flash enabled browser or a website specific app. On Android you will only be able to chat if the website provides an app for it.
The final important thing you need is a webcam. Many computers have a built in webcam, often of moderate or bad quality. If you do not have a lot of money to spend you should not bother too much about that. You can start with a low quality cam and try to save up money to buy a better quality cam later. Cams come in different qualities and a wide price range. A very cheap cam will cost you only about $10, the best consumer quality cams will cost about $130.
If you want to make money and work in a semi professional way it is advisable to buy a top range consumer cam. Some have full HD (1080p) quality and software that adjusts the light so your face will allways be well lit and well visible.
Many professional cam studio setups use basically these high end consumer / (semi) professional webcams. Above that you can get even better quality webcams, conference cams or video cameras with an optical zoom lense and remote control. But they will be more expensive and difficult to buy. You have to ask yourself if you really need a thing like that.
ID and bank account
All websites with a payment system we know require subscribers to be at least 18 years old. Most will ask an identification somewhere in the process. Be it when you subscribe, or when you want to cash the money you made. Sites who do not require an explicit age verification are often more difficult to enter by younger broadcasters than sites who do. They want to be on the safe side. Therefore broadcasters who are old enough but look younger may be banned from the site without appeal.
Obviously to cash tokens you need a bank account. Some (american) sites will send you a check, but there are also other methods of transferring the money to your bank account. Costs of international transfer and exchange to your local currency are usually for you. So depending on the payment method and your location, cashing $500 worth of credit may get you only $495 or $480 (or less?) worth of local currency.
Being female helps. Most sites will allow men, women, transgenders and mixed gender couples and groups to broadcast. So technically your gender does not really matter. But if you are female the chances of making money are highest.
You do not have to buy special software to chat. Most webcam chat sites run on a normal internet browser and require Adobe Flash Player. Adobe Flash Player is free. Because you also need it on game sites and video sites there is a good chance you already have it on your computer.
Normally you can only use your webcam in one program at a time. If you want to be active on more than one website simultaneously you will need cam splitter software. The most well known cam splitters are ManyCam and SplitCam. Both ManyCam and SplitCam have free versions available. Both are very good and in most cases more than sufficient to allow you to do what you want.
Some webcams will have accompanying software that allows you to use the features of the cam to a higher extent.