Set up your recording area by placing your microphone on a stand, about six inches to one foot in front of the heavy blanket. The blanket itself should be in the middle of a room, at least a few inches away from any wall. The blanket's purpose is to absorb sound reflections from the room to isolate the dialogue voice.
Connect your microphone to your computer input. This may require a mixer or other interface device. Microphones with built-in USB interfaces are now available from many manufacturers.
Set your pop filter in place, if you are using one, within an inch or two of the microphone. Arrange the mic so that your dialogue artist is four to six inches in front of the pop filter. Have the artist read some dialogue while you set levels using either your audio interface or a software input mixer. Listen for room sounds and adjust the blanket if necessary.
Record the dialogue using your audio editing software. It is advisable to record several versions of the dialogue so you can composit the best parts of each performance. Depending on the intended use of your dialogue, you may wish to add compression, equalization, reverb or other effects to your voices. It is usually best to add such signal processing after recording.