If you are an active trader that has a long history of successful trades, you may be tempted to start your own trading signal service. If you have a profitable trading system, or have developed a trading robot that others could benefit from, then this could become a great way to supplement you trading account.
One of the first things you should start testing is a trade copier. Most use MT4 and can copy trades to the people that subscribe to your service.
You may need to get a merchant account to process credit cards as not everyone uses Paypal. Signal services can also be considered higher risk because of the number of possible charge backs by customers, so merchant providers may charge higher fees.
Some merchants providers specialize in higher risk accounts, you can try GISO as a start, with the other major players being instabill.com and billpro.com.
Next you will need to actively market your signal service in order to get customers, so setup a WordPress website with a decent theme, woothemes.com have number of nice themes, and start writing your sales page.
Make sure your sales copy and service complies with the new NFA FIFO regulations.
You can then capture email leads of interested traders and follow them up with an email autoresponder series on the benefits of using your system.
Once your website and landing page is in place, use SEO and PPC advertising to attract visitors. PPC for forex related terms is not cheap, so consider writing some good quality forex tutorials to attract natural search traffic.
You can now use your MT4 EA and the trade copier to start sending trading signals to your customers.
It takes a fair amount of time to setup a signal service. If you use an automated trading robot and a trade copier, the on going maintenance is minimal, and you can spend the extra time marketing your service. The main thing is that you provide real value to your customers and in doing so build trust, that will translate into solid testimonials.