Download and install audio/visual editing software. There are many programs available for editing audio and visual. Some companies sell audio editors specifically for the purpose of creating subliminal messages. Companies such as Microsoft, Corel, Adobe and Roxio sell software for graphic and video editing. If you are on a budget, there are open source editing programs available for audio and video editing. You can search for open source software at websites like Post GRE SQL and Web Resources Depot.
Select media for embedding. Subliminal messages can be placed in pictures, videos, songs and spoken word recordings. Which media you choose to use depends on the type of messages you want to create. Visual subliminals are embedded as hidden images (in pictures) and spliced-in frames (in videos). Audio subliminals are hidden tracks that are too low to be consciously detected.
Record or draw the message. Visual subliminals can be drawn using graphic editing software. Audio subliminals must be recorded with a microphone and recording software. The most effective visual subliminals are simple phrases typed clearly in plain lettering. These are inserted into videos as hidden frames. Audio subliminals should ideally be spoken in a clear, slow, monotonous voice. Record any audio in a quiet, distraction-free area (a sound studio is ideal; a basement can suffice).
Edit frames into visual media. Most video editing programs give you the option of viewing video frame by frame, and let you splice frames in and out of the recording. To splice a frame in, simply select "insert frame" and upload the image you wish to use. Some video editors require that inserted frames be of a specific file format. If that is the case, simply load your image in the graphics editor, and save it in the required file type.
Edit subliminal tracks into audio media. Editing new audio tracks into a file is a fairly straightforward process. Most audio editors show a graph of the audio levels for a track. To splice in a second track, open your spoken subliminal audio track and select the entire file using the left mouse button. Click "Control C" to copy the audio. When you go to the audio file for the target track, you should have the option of adding a second track. This will create a second, empty graph beneath the initial graph. Paste the subliminal audio into the second graph and lower the frequency to the point that it cannot be consciously heard over the main audio file.
Preview the messages. Play the files in your video or audio player and make sure that the messages cannot be consciously detected. If you can see the subliminal frames or tracks clearly, return to the editing software to reduce the frame count or frequency level.