Study your target audience because FM radio tends to appeal to a niche market. Listen to broadcasts from the FM station to give you an idea of the sort of audience the programs would appeal to. If, for instance, the FM station specializes in jazz, you may want to put together a report on the history of the genre, supplemented with examples from the different eras.
Do your research into the subject matter of your broadcast. Take notes on the points you want to cover and note any areas that require you to find more information so you can better explain it to your audience. Creating an FM broadcast requires you to be conversant on the topic you are presenting. No matter if you are reporting on current market trends or giving people cooking advice, know your subject matter.
Organize your presentation. Just as writing an essay requires you to have topics logically arranged, the same is true for creating an FM broadcast. If you are doing an interview, have your questions written down so that you know exactly what you are going to ask your studio guest. If you are doing a report on yoga, you may want to intersperse the monologue with music for more variety.
Do a trial broadcast. Gather your material and record your FM broadcast. Then play it back and listen to your tone of voice, speed of delivery and pronunciation of words. Assess if you sounded knowledgeable about the topic. Revise accordingly and do another test run if you want to perfect your on-air delivery.
Test your equipment -- make sure the headphones are plugged in -- and check the volume level before you go to air. There is nothing more annoying than having to listen to "Test 1, 2, 3," so make sure everything is operational before the red light goes on ten seconds prior to broadcast time.
Develop a relationship with your listening audience. Speak in a personal tone and invite your listeners to join you. If you are doing a phone-in segment, always be polite and allow people to express their opinions before you cut in.