To be a success at hosting a radio show, like anything else in life, requires a level of skill combined with preparation and passion for the craft. The common myth is hosting a radio show is 'just talking for an hour or two about a topic'. The reality is that most hosts take longer to prepare then they actually talk on-air.
To have a smooth running show with good momentum, you need a plan and an outline for the hour. It is good to think of each segment as its own 'mini show'. You want to stay topical with every segment. The topic needs to be clear and easily digestible for the listener. The average listener may stick around for 20 to 30 minutes so you have to give them a 'good show' and some killer content while they are tuned-in.
Every radio segment in an hour should stand by itself, have a brief monologue to introduce the topic, make your points and wrap it up before the commercial. Then you can 'tease' the subject of the next segment. It is fine if you have the same topic for the whole hour, just break it out into 4 facets of that topic for each segment.
It is live radio, so momentum and spontaneity are part of the process. Be careful not to script your talking points too much. A better idea is to work off an outline with notes as reference. It is ok to have a brief monologue scripted to open the show or read an excerpt from an article of interest. The audience can tell the difference between when you’re genuine and when you’re reading a script.
In case a listener has tuned in mid-segment, it is always good to do a recap. You pause in the middle and remind the audience what station and show they are listening to, the topic and any major points that already been made. Then you jump right back into the action. The mid-point of a segment also can be a good time to give out the call-in number and invite the listeners to 'join the conversation'. Likewise, if you are interviewing someone, you can remind the audience who you are talking to and ask for relevant questions.
Remember you are a radio host, there to inform and entertain the audience. Your personality and content must engage the listeners to build an audience. It is all about connection with the listener and keeping his or her attention. The audience wants to be involved. It is about the listener's experience more than your own. If you do not connect with the listeners, or if the listener does not buy in to the topic, they will not stick around.
Often overlooked is your physical set up. Sit up in your chair (or even stand) and have good posture when hosting. People will hear your energy in your voice and get excited. Get your coffee, prep mentally for the show and come out strong. At the end of the show, you should feel a little tired, talking your passion for the show topic.
Lastly, Have Fun! Radio is a great and personal medium that helps a host to easily touch base with a variety of listeners.