What're Forex trade signals? They're paid services offered by brokers and forex analysts. Their job is to observe and evaluate, then alert you on their data regularly.
When preparing data, several factors are taken into account. They'll do a technical analysis of market conditions and use different indicators to detect trends and identify time to buy and sell. They'll then send this data to you in any form and place you choose. it's up to you to act on the information given. Let it pass.
Most of the signal services offer the more popular currency pair such as EUR / USD. However, it's possible to subscribe to the less popular traded pairs from speciality services.
Forex signals can be rather expensive, over 100USD a month. The benefit of having this service is that the forex data would be analysed on your behalf, saving you a lot of time. However, this service is no substitute for knowledge of forex market. They can only provide data. The decision is still in your hands.
Finding a suitable signal service may be tricky. You should request their historical data. You can view their success and failure record yourself. You mustn't however, be put off by failure as you must bear in mind that forex signal services also have losing trades. They're purely additional help, not your decision makers. You mustn't expect the presence of a signal service will insure profits. View it as another member in your trading team.