Starting the emulator from an IDE typically happens by fist configuring the emulator for the IDE in question and then running an application from the IDE. This will open the emulator, in which you can then view the application in question.
The S60 5th Edition SDK supports the following IDEs:
Notice, that only winscw builds of applications can be run on the S60 emulator. You can create such builds in the supported IDEs.
EclipseME version 1.6.6 (or later)
Notice that the emulator is only able to run applications packaged into a MIDlet Suite as specified in the MIDP specification. This means that both a JAD file (Java Application Descriptor) and a JAR file (Java Archive) must be created before running the application.
For more information on how to run applications from supported IDEs, see Using the SDK with an IDE.