You are looking for service that will allow you to share your signals and trades with another trades?
What do you mean as “service”: a tecnhical solution or a platform like a community to find subsricbers?
If you are speaking about technical solution, pay attention to the Forex Copier (Remote edition). In consists from two parts, each for signals provider and the customert. As far as I know, it is the most popular and useful tool for such purpose.
At the same time, if you are looking for potential subscibers, you can check the forex trading forums - each has special section dedicated to trading signals. For sure, you will need to prove that your signals are reliable and profitable.