It's really scary to clip with scissors. If you decide to go this route, be sure to only cut level with the skin. And don't pull the hair because this lifts the skin and will pull it into the blades of the scissors.
Instead, I would buy a clipper set (cheap one is 19.99 at walmart). Then use this (comes with an instructional video) to trim her. It takes some practice but it can help prevent mats between vet visit.
Let me know if you still have questions.
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