First. It's called stretching, not "gauging". Gauge refers to the size of the jewelry, you have 0 gauge plugs, or 14 gauge rings, or whatever. Stretching is what you do when you go up a size.
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Listen to your body. If you feel anything other than a slight discomfort, you're probably going to fast. If it hurts, gets swollen, or even worse bleeds, you're going way too fast. My ears have been at an inch now for years but when I was stretching, sometimes I could wait a couple weeks and be able to stretch, sometimes it took over a month. A couple times I got in a hurry and blew out my ears, and trust me, it's no fun. With my septum, stretched to a 6 from 12, I was able to stretch every 3 weeks or so as it seemed to heal up quicker than my earlobes. Everyones body is different, and some people heal faster than others. A month between stretches seems to work for most though.
When you think you're ready to stretch, try to put the new plugs in while taking a hot shower. The steam will loosen your skin a bit more than it already is, and if your ears are ready for it, will make it even easier.