Anyone know how to resize a skirt from 18 to 10? (UK sizes)

I bought a heap of skirts at the charity shop recently, more for their zips & fabric than anything else, but one of them I like and now want to wear it. It's too big (size 18) which currently sits a bit loose on my hips, and I need help to alter it to make it sit more on my waist, or just below - preferably in the form of a how-to video! It's a non-elastic waistband, with a zip. It's also too long, but I was going to cut it & hem it with lace to hide my wobbly stitching!

Edit - It's also lined, with the lining in the waistband, so if I cut out the waistband I'll have to redo the lining too. Maybe I could put pleats in the front of the skirt?

Get your seam ripper and undo every seam (waistband  and zipper included).  Now pin the skirt side seams wrong sides together, but with seam allowances increased by at least an inch.  See how it fits.  Adjust accordingly. 

Now cut off the excess being careful to follow the angles of the side seam allowances.  You may want to mark the cutting line with a pencil or marker first.

Re-sew the side seams, and re-attach the zipper in the normal way.

Re attach the waistband, cutting off the excess in the same way you did the side seams.

Finish the seams, add button or snap if necessary.