Well, strictly speaking it's not dressmaking but skirt making and French knicker making. I signed up for (yet another) Craftsy course - Sew Ready: Garment Basics with Brett Bara. It was BRILLIANT! It concentrates on skirt making and the skirt pattern is included in the price (it took 2 or 3 weeks to get to the UK from the USA) but it is a thorough and simple course taught by an enthusiastic teacher. You are taken through each step of making the skirt, covering things like cutting the pattern shapes, seam treatments, adding facings, darts and the simplest instructions for adding a zipper that I have ever seen. I used calico/muslin to make my skirt and made it shorter than I would usually wear (just because I'm cheap and didn't want to waste good fabric if it was all going to go wrong) but it is undoubtedly the right shape.
The French knickers were not quite as successful, mainly due to my elastic sewing skills not being very good. There is too much stretch in the elastic after I'd stitched it in so the knickers won't actually stay up. Not the ideal pair of underwear. However, it hasn't put me off dressmaking. I have now signed up for Pant Construction Techniques so no doubt I'll be writing about how that course goes soon.