the first thing you'll need is some tools. you'll need an instrument (for this one I use a Yamaha DSR-500 keyboard). a good working mic (I'm using a Blue Yeti mic http://bluemic.com/yeti/) that can hook up to a computer and the Adobe Audition program to record.
once every thing is in order start up Adobe Audition
Step 1: Adobe Adition
To Make sure the mic is plugged in and working press the R button in Track 1 to arm the mic.
The R should be red showing its working.
Tap the mic a couple times and Green coloured bars should spring up leting you know the sound is working.
Step 2: Lets Lecord Music
Step 3: Edit the Sound
when you want to export the sound you just created click file, go down to export, click multitrack mixdown and entire session
now you can use the music or sound you created for almost anything you want.