I've sewn clothing for years, and just recently have tried quilting. I would suggest that before you start on the vintage dress, buy a quick to make dress pattern in a simple style and make that. Also, you'll find that the vintage pattern may have some instructions that are harder to follow, thus making the simple dress first will help you to understand how everything fits together. Good luck with this ... dressmaking is rewarding. Also, if you are concerned about the fit, try making the dress from unbleached muslin for the fit, and then adjust as needed.