Embroidery on Wedding Dress

My DD called yesterday and said that she would like to to add blue highlights to her casual wedding dress and the same to groom's shirt. I'm HONORED, but suddenly I'm very concerned about my skills! Been a long time since I did straight embroidery. I'll wait to see what type of pattern is on the dress, then attempt to duplicate on shirt. I'm already debating the wisdom of stitching directly on the shirt vs stitching on fabric to tack on to it - just in case Mr. Frog comes for a long visit. I've already decided it's going to be washable silks!