Let me start by saying thank you so much for running this website,  it is really an invaluable resource.  I especially like the way you go step by step through the whole creative process from pattern envelope to finished product.  You rock!

So my question….I notice in most of your tutorials, you do not trim the seam allowances after sewing the seam, but leave them at 5/8 thickness.   After I sew a seam, press it, then press it open, do I need to do anything else to it?  I am making a dress for my daughter, it is a lined dress.  Cotton blend with a broadcloth lining.  When I did my last dress for my other daughter which was eyelet on the outside and with a broadcloth lining, I stitched the seam, then pressed it, but then I didn’t press it open, but did a zigzag stitch close to the seamline, then trimmed it close to the zigzag stitching.  So essentially I zigzagged the seam allowances together, then trimmed them.  I was so paranoid that the material would ravel so I was trying to go for the homemade version of what you see with commercial serged seams.  Is this necessary?  Is this overkill?  Do I only need to trim and finish the seams when the pattern indicates?

Thanks in advance for your response and keep up the good work!