java org.microemu.app.Main (MIDlet application main class) or java org.microemu.app.Main (MIDlet jad file)
java -cp microemulator.jar;YourApp.jar org.microemu.app.Main com.yourcompany.YourMidlet or java -cp microemulator.jar org.microemu.app.Main path2yourApp/YourApp.jad
java -jar microemulator.jar (MIDlet application main class) or java -jar microemulator.jar (MIDlet jad file)
java -cp microemulator.jar;microemu-nokiaui.jar;YourApp.jar org.microemu.app.Main com.yourcompany.YourMidlet or java -cp microemulator.jar;microemu-siemensapi.jar org.microemu.app.Main http://wwww.yourcompany.com/download/YourApp-sim.jad
MicroEmulator command line options
Other examples
java -cp microemulator.jar;microemu-device-large.jar org.microemu.app.Main --device org/microemu/device/large/device.xml http://wintermute.de/wap/5ud0ku.jad
MicroEmulator with JSR
java -cp microemulator.jar;bluecove-1.2.3.jar org.microemu.app.Main btbrowserv20.jad
All you need to do is to configure Run Command to start Emulator Directly from the IDE.
Click on your project, go to Run > Run.
Double click "Java Application" to create a run type. Name this new run command.
For Main class, put in> org.microemu.app.Main and select "Include libraries when searching for main class" .

Click the "Argument" tab and this under Program arguments enter you MIDlet class name.

If your MIDlet project includes other projects or libraries that are compiled differently and included in you final application. e.g. XML or Log libraries. Then you need to add aditional configuration option. MicroEmulator will use the same MIDlet classloader for this clases. If not specified this classes would be loaded by the same classloader as MicroEmulator e.g. SystemClassLoader.
--appclasspath /home/bob/work/framework0.1.jar;/home/bob/work/core/target/classes org.app.MainMIDlet
More convenient option is to let MicroEmulator detect the location of the classes in project classpath. Only one class name from each library or project needs to be specified.
--appclass org.framework.OneClass --appclass org.core.AnotherClass org.app.MainMIDlet
Finally, go to the class path, add your project (done already by default), and add microemulator.jar (under User Entries)
The described above approach is working when your project is EclipseME project. In this case you need to specify Runtime JRE.
Select Execution Environment: J2SE-1.4, J2SE-1.5 or JavaSE-1.6

As of EclipseME version 1.7.0 it has its own support for MicroEmulator. Import MicroEmulator installation directory using Window -> Preferences -> J2ME -> Device Management Then just select MicroEmulator as J2ME Device using EclipseME menus and properties.