Sewing

I would start with a buffet place like Ryan’s. Some Hardee’s thick burgers should finish the job

If it's just a matter of the waist sliding off your hips, you can usually turn the skirt inside out, make a triangle with the excess waistline being one side and the opposite point being the hem, and then sew the crease like that. If you have details you would like to keep centered, do it twice, one on each side, with half the excess instead. I'd probably do this at the sides, where your hips would be.

Once that's done, you can decide if you want to remove the triangles or not. If you don't, you'll have the option of letting it out again at a later date if necessary, but you'll have those bits of fabric on the inside to deal with.

If the skirt is pleated, you can skip the triangle step and just sew the waistline excess together.

I'd turn it inside out and put it on, pinch the sides or back until the waist fits comfortably, then use safety pins to hold it together. It would be best to make this fold along a pre-existing seam.

After that take the pinned skirt, place it flat, and use something (washable marker or a sliver of soap work well) to draw a making line from the top of the waist to the fold. Use the safety pin as a guide for where to put the line.

After that you can just sew a straight stitch along your line all the way from fold to waist. Make sure to use some good sturdy thread. This is easier if you have access to a sewing machine, but if you don't and need to hand sew it here's a tutorial I found for a simple straight line.

After that try it on again and if it fits you can cut away the excess fabric. Otherwise, use a small pair of scissors to cut your stitches and redraw your line to be further or closer to the fold depending on the fit.

Easy. Make them smaller.

A tailor should help you sort your challenges.