This doll is designed to be baby-safe. I use 5 mm safety eyes. You can choose to embroider the eyes and smile. Gauge isn’t necessary for this pattern. However, I recommend a tight stitch to keep any stuffing from coming out. This pattern is for the doll only. I leave it to the crocheter to choose which hat best suits the child’s personality. Size will depend largely on your tension and the yarn you choose. Not all worsteds are created equal!