If I understand what you're asking...I'd say you don't.
Instead, go here...
Go to... File > Settings > Program Settings OR simply hit the 'Y' key.
At the lower right corner of the Program Settings dialog box, click on the box to check the "Hide instruments which remain empty in the style selection" setting.
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All you got to do .... is go to the soundpool list, select one from the list like (ambient, trance, rock, moviescore, etc.). Select the main one, and press ALT + DEL button... and you are good !!
I had same problem and found out the solution .... thanx