I hope I'm not coming off as a smart ass as I suspect some people don't know this.
For as long as you don't click confirm/ok/whatever button it is(I forget), you can mess around in the makeover room. You can save your settings, and then cancel and still retain your scroll. Then you can go back in bring up your saved settings and do more tweaking, and cancel/repeat until you get the desired look. Think of it as holding on to it as you can.
And yeah the 30 minute cooldown is annoying.