Here is how I made my red skirt to wear with a black top and trousers.
First I sewed together a strip of black elastic which I roughly measured around my waist.
Next I cut lengths of red tulle. I measured the approximate length I wanted my skirt to be and then doubled this before cutting.
I then passed the doubled length through the black elastic and back on itself to secure, pulling it tight to hold into position.
I repeated this around the skirt before applying some black felt circles (which were actually bought as feet pads for furniture) to make the spots.
Here is the finished skirt!