Cut just enough from Barbie to cover your mustache, plus one inch. In this case, I wanted to do a goatee from the beards template, so I cut long pieces of hair to lay over both the goatee and the mustache. Snip the hair in small bunches so that it is easier to handle.
If you want to get out some childhood angst while chopping her hair, that's up to you. Personally, I called my mom and told her exactly what I was doing. Then I ate ice cream for dinner and told her about that, too. Next, we will coat the baggie in rubber cement.
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