How do I hide scars?

So, I struggle with self harm—I don’t know what the scale is, but I’ve been told it’s particularly gruesome to see my scars. I’m a dancer, so I’ve kept it to the areas just above my legs on my hips, but I’m going to a big national event in a month, and I won’t be able to get out of wearing ballet tights. I’ve stopped actively harming for now, so that everything is at least healed by then, but my leotard doesn’t cover it and the tights aren’t opaque. Does anyone know how I could hide it without offending an instructor?